Electric and magnetic forces have been known since antiquity, but they were regarded as separate phenomena for centuries. Magnetism was studied experimentally at least as early as the 13th century; the properties of the magnetic compass undoubtedly aroused interest in the phenomenon. Systematic investigations of electricity were delayed until the invention of practical devices for producing electric charge and currents. As soon as inexpensive, easy-to-use sources of electricity became available, scientists produced a wealth of experimental data and theoretical insights. As technology advanced, they studied, in turn, magnetism and electrostatics, electric currents and conduction, electrochemistry, magnetic and electric induction, the interrelationship between electricity and magnetism, and finally the fundamental nature of electric charge.
The oldest practical application of magnetism was the magnetic compass, but its origin remains unknown. Some historians believe it was used in China as far back as the 26th century bce; others contend that it was invented by the Italians or Arabs and introduced to the Chinese during the 13th century ce. The earliest extant European reference is by Alexander Neckam (died 1217) of England.
The first experiments with magnetism are attributed to Peter Peregrinus of Maricourt, a French Crusader and engineer. In his oft-cited Epistola de magnete (1269; "Letter on the Magnet"), Peregrinus described having placed a thin iron rectangle on different parts of a spherically shaped piece of magnetite (or lodestone) and marked the lines along which it set itself. The lines formed a set of meridians of longitude passing through two points at opposite ends of the stone, in much the same way as the lines of longitude on Earth's surface intersect at the North and South poles. By analogy, Peregrinus called the points the poles of the magnet. He further noted that, when a magnet is cut into pieces, each piece still has two poles. He also observed that unlike poles attract each other and that a strong magnet can reverse the polarity of a weaker one.
The founder of the modern sciences of electricity and magnetism was William Gilbert, physician to both Elizabeth I and James I of England. Gilbert spent 17 years experimenting with magnetism and, to a lesser extent, electricity. He assembled the results of his experiments and all of the available knowledge on magnetism in the treatise De Magnete, Magneticisque Corporibus, et de Magno Magnete Tellure ("On the Magnet, Magnetic Bodies, and the Great Magnet of the Earth"), published in 1600. As suggested by the title, Gilbert described Earth as a huge magnet. He introduced the term electric for the force between two objects charged by friction and showed that frictional electricity occurs in many common materials. He also noted one of the primary distinctions between magnetism and electricity: the force between magnetic objects tends to align the objects relative to each other and is affected only slightly by most intervening objects, while the force between electrified objects is primarily a force of attraction or repulsion between the objects and is grossly affected by intervening matter. Gilbert attributed the electrification of a body by friction to the removal of a fluid, or "humour," which then left an "effluvium," or atmosphere, around the body. The language is quaint, but, if the "humour" is renamed "charge" and the "effluvium" renamed "electric field," Gilbert's notions closely approach modern ideas.
During the 17th and early 18th centuries, as better sources of charge were developed, the study of electric effects became increasingly popular. The first machine to generate an electric spark was built in 1663 by Otto von Guericke, a German physicist and engineer. Guericke's electric generator consisted of a sulfur globe mounted on an iron shaft. The globe could be turned with one hand and rubbed with the other. Electrified by friction, the sphere alternately attracted and repulsed light objects from the floor.
Stephen Gray, a British chemist, is credited with discovering that electricity can flow (1729). He found that corks stuck in the ends of glass tubes become electrified when the tubes are rubbed. He also transmitted electricity approximately 150 metres through a hemp thread supported by silk cords and, in another demonstration, sent electricity even farther through metal wire. Gray concluded that electricity flowed everywhere.
From the mid-18th through the early 19th centuries, scientists believed that electricity was composed of fluid. In 1733 Charles François de Cisternay DuFay, a French chemist, announced that electricity consisted of two fluids: "vitreous" (from the Latin for "glass"), or positive, electricity; and "resinous," or negative, electricity. When DuFay electrified a glass rod, it attracted nearby bits of cork. Yet, if the rod touched the pieces of cork, the cork fragments were repelled and also repelled one another. DuFay accounted for this phenomenon by explaining that, in general, matter was neutral because it contained equal quantities of both fluids; if, however, friction separated the fluids in a substance and left it imbalanced, the substance would attract or repel other matter.
In 1745 a cheap and convenient source of electric sparks was invented by Pieter van Musschenbroek, a physicist and mathematician in Leiden, Netherlands. Later called the Leyden jar, it was the first device that could store large amounts of electric charge. (E. Georg von Kleist, a German cleric, independently developed the idea for such a device but did not investigate it as thoroughly as Musschenbroek did.) The Leyden jar devised by the latter consisted of a glass vial that was partially filled with water and contained a thick conducting wire capable of storing a substantial amount of charge. One end of this wire protruded through the cork that sealed the opening of the vial. The Leyden jar was charged by bringing this exposed end of the conducting wire into contact with a friction device that generated static electricity.
Within a year after the appearance of Musschenbroek's device, William Watson, an English physician and scientist, constructed a more-sophisticated version of the Leyden jar; he coated the inside and outside of the container with metal foil to improve its capacity to store charge. Watson transmitted an electric spark from his device through a wire strung across the River Thames at Westminster Bridge in 1747.
The Leyden jar revolutionized the study of electrostatics. Soon "electricians" were earning their living all over Europe demonstrating electricity with Leyden jars. Typically, they killed birds and animals with electric shock or sent charges through wires over rivers and lakes. In 1746 the abbé Jean-Antoine Nollet, a physicist who popularized science in France, discharged a Leyden jar in front of King Louis XV by sending current through a chain of 180 Royal Guards. In another demonstration, Nollet used wire made of iron to connect a row of Carthusian monks more than a kilometre long; when a Leyden jar was discharged, the white-robed monks reportedly leapt simultaneously into the air.
In America, Benjamin Franklin sold his printing house, newspaper, and almanac to spend his time conducting electricity experiments. In 1752 Franklin proved that lightning was an example of electric conduction by flying a silk kite during a thunderstorm. He collected electric charge from a cloud by means of wet twine attached to a key and thence to a Leyden jar. He then used the accumulated charge from the lightning to perform electric experiments. Franklin enunciated the law now known as the conservation of charge (the net sum of the charges within an isolated region is always constant). Like Watson, he disagreed with DuFay's two-fluid theory. Franklin argued that electricity consisted of two states of one fluid, which is present in everything. A substance containing an unusually large amount of the fluid would be "plus," or positively charged. Matter with less than a normal amount of fluid would be "minus," or negatively charged. Franklin's one-fluid theory, which dominated the study of electricity for 100 years, is essentially correct because most currents are the result of moving electrons. At the same time, however, fundamental particles have both negative and positive charges and, in this sense, DuFay's two-fluid picture is correct.
Joseph Priestley, an English physicist, summarized all available data on electricity in his book History and Present State of Electricity (1767). He repeated one of Franklin's experiments, in which the latter had dropped small corks into a highly electrified metal container and found that they were neither attracted nor repelled. The lack of any charge on the inside of the container caused Priestley to recall Newton's law that there is no gravitational force on the inside of a hollow sphere. From this, Priestley inferred that the law of force between electric charges must be the same as the law for gravitational force—i.e., that the force between masses diminishes with the inverse square of the distance between the masses. Although they were expressed in qualitative and descriptive terms, Priestley's laws are still valid today. Their mathematics was clarified and developed extensively between 1767 and the mid-19th century as electricity and magnetism became precise, quantitative sciences.
Priestley, Joseph: electricity generation and storageApparatus designed by Joseph Priestley for the generation and storage of electricity, from an engraving by Andrew Bell for the first edition of the Encyclopædia Britannica (1768–71). By means of a wheel connected by string to a pulley, the machine rotated a glass globe against a "rubber," which consisted of a hollow piece of copper filled with horsehair. The resultant charge of static electricity, accumulating on the surface of the globe, was collected by a cluster of wires (m) and conducted by brass wire or rod (l) to a "prime conductor" (k), a hollow vessel made of polished copper. Metallic rods could be inserted into holes in the conductor "to convey the fire where-ever it is wanted." Encyclopædia Britannica, Inc.
The mathematicians Siméon-Denis Poisson of France and Carl Friedrich Gauss of Germany extended Coulomb's work during the 18th and early 19th centuries. Poisson's equation (published in 1813) and the law of charge conservation contain in two lines virtually all the laws of electrostatics. The theory of magnetostatics, which is the study of steady-state magnetic fields, also was developed from Coulomb's law. Magnetostatics uses the concept of a magnetic potential analogous to the electric potential (i.e., magnetic poles are postulated with properties analogous to electric charges).
Michael Faraday built upon Priestley's work and conducted an experiment that verified quite accurately the inverse square law. Faraday's experiment involving the use of a metal ice pail and a gold-leaf electroscope was the first precise quantitative experiment on electric charge. In Faraday's time, the gold-leaf electroscope was used to indicate the electric state of a body. This type of apparatus consists of two thin leaves of gold hanging from an insulated metal rod that is mounted inside a metal box. When the rod is charged, the leaves repel each other and the deflection indicates the size of the charge. Faraday began his experiment by charging a metal ball suspended on an insulating silk thread. He then connected the gold-leaf electroscope to a metal ice pail resting on an insulating block and lowered the charged ball into the pail. The electroscope reading increased as the ball was lowered into the pail and reached a steady value once the ball was within the pail. When the ball was withdrawn without touching the pail, the electroscope reading fell to zero. Yet when the ball touched the bottom of the pail, the reading remained at its steady value. On removal the ball was found to be completely discharged. Faraday concluded that the electric charge produced on the outside of the pail, when the ball was inside but not in contact with it, was exactly equal to the initial charge on the ball. He then inserted into the pail other objects, such as a set of concentric pails separated from one another with various insulating materials like sulfur. In each case, the electroscope reading was the same once the ball was completely within the pail. From this Faraday concluded that the total charge of the system was an invariable quantity equal to the initial charge of the ball. The present-day belief that conservation is a fundamental property of charge rests not only on the experiments of Franklin and Faraday but also on its complete agreement with all observations in electric engineering, quantum electrodynamics, and experimental electricity. With Faraday's work, the theory of electrostatics was complete.
The invention of the battery in 1800 made possible for the first time major advances in the theories of electric current and electrochemistry. Both science and technology developed rapidly as a direct result, leading some to call the 19th century the age of electricity.
The development of the battery was the accidental result of biological experiments conducted by Luigi Galvani. Galvani, a professor of anatomy at the Bologna Academy of Science, was interested in electricity in fish and other animals. One day he noticed that electric sparks from an electrostatic machine caused muscular contractions in a dissected frog that lay nearby. At first Galvani assumed that the phenomenon was the result of atmospheric electricity because similar effects could be observed during lightning storms. Later he discovered that whenever a piece of metal connected the muscle and nerve of the frog, the muscle contracted. Although Galvani realized that some metals appeared to be more effective than others in producing this effect, he concluded incorrectly that the metal was transporting a fluid, which he identified with animal electricity, from the nerve to the muscle. Galvani's observations, published in 1791, aroused considerable controversy and speculation.
Alessandro Volta, a physicist at the nearby University of Pavia, had been studying how electricity stimulates the senses of touch, taste, and sight. When Volta put a metal coin on top of his tongue and another coin of a different metal under his tongue and connected their surfaces with a wire, the coins tasted salty. Like Galvani, Volta assumed that he was working with animal electricity until 1796 when he discovered that he could also produce a current when he substituted a piece of cardboard soaked in brine for his tongue. Volta correctly conjectured that the effect was caused by the contact between metal and a moist body. Around 1800 he constructed what is now known as a voltaic pile consisting of layers of silver, moist cardboard, and zinc, repeated in that order, beginning and ending with a different metal. When he joined the silver and the zinc with a wire, electricity flowed continuously through the wire. Volta confirmed that the effects of his pile were equivalent in every way to those of static electricity. Within 20 years, galvanism, as electricity produced by a chemical reaction was then called, became unequivocally linked to static electricity. More important, Volta's invention provided the first source of continuous electric current. This rudimentary form of battery produced a smaller voltage than the Leyden jar, but it was easier to use because it could supply a steady current and did not have to be recharged.
The controversy between Galvani, who mistakenly thought that electricity originated in the animal's nerve, and Volta, who realized that it came from the metal, had divided scientists into two camps. Galvani was supported by Alexander von Humboldt in Germany, while Volta was backed by Coulomb and other French physicists.
Within six weeks of Volta's report, two English scientists, William Nicholson and Anthony Carlisle, used a chemical battery to discover electrolysis (the process in which an electric current produces a chemical reaction) and initiate the science of electrochemistry. In their experiment the two employed a voltaic pile to liberate hydrogen and oxygen from water. They attached each end of the pile to brass wires and placed the opposite ends of the wires into salt water. The salt made the water a conductor. Hydrogen gas accumulated at the end of one wire; the end of the other wire was oxidized. Nicholson and Carlisle discovered that the amount of hydrogen and oxygen set free by the current was proportional to the amount of current used. By 1809 the English chemist Humphry Davy had used a stronger battery to free for the first time several very active metals—sodium, potassium, calcium, strontium, barium, and magnesium—from their liquid compounds. Faraday, who was Davy's assistant at the time, studied electrolysis quantitatively and showed that the amount of energy needed to separate a gram of a substance from its compound is closely related to the atomic weight of the substance. Electrolysis became a method of measuring electric current, and the quantity of charge that releases a gram atomic weight of a simple element is now called a faraday in his honour.
Once scientists were able to produce currents with a battery, they could study the flow of electricity quantitatively. Because of the battery, the German physicist Georg Simon Ohm was able experimentally in 1827 to quantify precisely a problem that Cavendish could only investigate qualitatively some 50 years earlier—namely, the ability of a material to conduct electricity. The result of this work—Ohm's law—explains how the resistance to the flow of charge depends on the type of conductor and on its length and diameter. According to Ohm's formulation, the current flow through a conductor is directly proportional to the potential difference, or voltage, and inversely proportional to the resistance—that is, i = V/R. Thus, doubling the length of an electric wire doubles its resistance, while doubling the cross-sectional area of the wire reduces the resistance by a half. Ohm's law is probably the most widely used equation in electric design.
One of the great turning points in the development of the physical sciences was Hans Christian Ørsted's announcement in 1820 that electric currents produce magnetic effects. (Ørsted made his discovery while lecturing to a class of physics students. He placed by chance a wire carrying current near a compass needle and was surprised to see the needle swing at right angles to the wire.) Ørsted's fortuitous discovery proved that electricity and magnetism are linked. His finding, together with Faraday's subsequent discovery that a changing magnetic field produces an electric current in a nearby circuit, formed the basis of both James Clerk Maxwell's unified theory of electromagnetism and most of modern electrotechnology.
Once Ørsted's experiment had revealed that electric currents have magnetic effects, scientists realized that there must be magnetic forces between the currents. They began studying the forces immediately. A French physicist, François Arago, observed in 1820 that an electric current will orient unmagnetized iron filings in a circle around the wire. That same year, another French physicist, André-Marie Ampère, developed Ørsted's observations in quantitative terms. Ampère showed that two parallel wires carrying electric currents attract and repel each other like magnets. If the currents flow in the same direction, the wires attract each other; if they flow in opposite directions, the wires repel each other. From this experiment, Ampère was able to express the right-hand rule for the direction of the force on a current in a magnetic field. He also established experimentally and quantitatively the laws of magnetic force between electric currents. He suggested that internal electric currents are responsible for permanent magnets and for highly magnetizable materials like iron. With Arago he demonstrated that steel needles become more strongly magnetic inside a coil carrying an electric current. Experiments on small coils showed that, at large distances, the forces between two such coils are similar to those between two small bar magnets and, moreover, that one coil can be replaced by a bar magnet of suitable size without changing the forces. The magnetic moment of this equivalent magnet was determined by the dimensions of the coil, its number of turns, and the current flowing around it.
William Sturgeon of England and Joseph Henry of the United States used Ørsted's discovery to develop electromagnets during the 1820s. Sturgeon wrapped 18 turns of bare copper wire around a U-shaped iron bar. When he turned on the current, the bar became an electromagnet capable of lifting 20 times its weight. When the current was turned off, the bar was no longer magnetized. Henry repeated Sturgeon's work in 1829, using insulated wire to prevent short-circuiting. Using hundreds of turns, Henry created an electromagnet that could lift more than one ton of iron.
Ørsted's experiment showing that electricity could produce magnetic effects raised the opposite question as well: Could magnetism induce an electric current in another circuit? The French physicist Augustin-Jean Fresnel argued that since a steel bar inside a metallic helix can be magnetized by passing a current through the helix, the bar magnet in turn should create a current in an enveloping helix. In the following decade many ingenious experiments were devised, but the expectation that a steady current would be induced in a coil near the magnet resulted in experimenters either accidentally missing or not appreciating any transient electric effects caused by the magnet.
Faraday, the greatest experimentalist in electricity and magnetism of the 19th century and one of the greatest experimental physicists of all time, worked on and off for 10 years trying to prove that a magnet could induce electricity. In 1831 he finally succeeded by using two coils of wire wound around opposite sides of a ring of soft iron (Figure 7). The first coil was attached to a battery; when a current passed through the coil, the iron ring became magnetized. A wire from the second coil was extended to a compass needle a metre away, far enough so that it was not affected directly by any current in the first circuit. When the first circuit was turned on, Faraday observed a momentary deflection of the compass needle and its immediate return to its original position. When the primary current was switched off, a similar deflection of the compass needle occurred but in the opposite direction. Building on this observation in other experiments, Faraday showed that changes in the magnetic field around the first coil are responsible for inducing the current in the second coil. He also demonstrated that an electric current can be induced by moving a magnet, by turning an electromagnet on and off, and even by moving an electric wire in Earth's magnetic field. Within a few months, Faraday built the first, albeit primitive, electric generator.
Figure 7: Faraday's magnetic induction experiment. When the switch S is closed in the primary circuit, a momentary current flows in the secondary circuit, giving a transient deflection of the compass needle M. Encyclopædia Britannica, Inc.
Henry had discovered electric induction quite independently in 1830, but his results were not published until after he had received news of Faraday's 1831 work, nor did he develop the discovery as fully as Faraday. In his paper of July 1832, Henry reported and correctly interpreted self-induction. He had produced large electric arcs from a long helical conductor when it was disconnected from a battery. When he had opened the circuit, the rapid decrease in the current had caused a large voltage between the battery terminal and the wire. As the wire lead was pulled away from the battery, the current continued to flow for a short time in the form of a bright arc between the battery terminal and the wire.
Faraday's thinking was permeated by the concept of electric and magnetic lines of force. He visualized that magnets, electric charges, and electric currents produce lines of force. When he placed a thin card covered with iron filings on a magnet, he could see the filings form chains from one end of the magnet to the other. He believed that these lines showed the directions of the forces and that electric current would have the same lines of force. The tension they build explains the attraction and repulsion of magnets and electric charges. Faraday had visualized magnetic curves as early as 1831 while working on his induction experiments; he wrote in his notes, "By magnetic curves I mean lines of magnetic forces which would be depicted by iron filings." Faraday opposed the prevailing idea that induction occurred "at a distance"; instead, he held that induction occurs along curved lines of force because of the action of contiguous particles. Later he explained that electricity and magnetism are transmitted through a medium that is the site of electric or magnetic "fields," which make all substances magnetic to some extent.
Faraday was not the only researcher laying the groundwork for a synthesis between electricity, magnetism, and other areas of physics. On the continent of Europe, primarily in Germany, scientists were making mathematical connections between electricity, magnetism, and optics. The work of the physicists Franz Ernst Neumann, Wilhelm Eduard Weber, and H.F.E. Lenz belongs to this period. At the same time, Helmholtz and the English physicists William Thomson (later Lord Kelvin) and James Prescott Joule were clarifying the relationship between electricity and other forms of energy. Joule investigated the quantitative relationship between electric currents and heat during the 1840s and formulated the theory of the heating effects that accompany the flow of electricity in conductors. Helmholtz, Thomson, Henry, Gustav Kirchhoff, and Sir George Gabriel Stokes also extended the theory of the conduction and propagation of electric effects in conductors. In 1856 Weber and his German colleague, Rudolf Kohlrausch, determined the ratio of electric and magnetic units and found that it has the same dimensions as light and that it is almost exactly equal to its velocity. In 1857 Kirchhoff used this finding to demonstrate that electric disturbances propagate on a highly conductive wire with the speed of light.
The final steps in synthesizing electricity and magnetism into one coherent theory were made by Maxwell. He was deeply influenced by Faraday's work, having begun his study of the phenomena by translating Faraday's experimental findings into mathematics. (Faraday was self-taught and had never mastered mathematics.) In 1856 Maxwell developed the theory that the energy of the electromagnetic field is in the space around the conductors as well as in the conductors themselves. By 1864 he had formulated his own electromagnetic theory of light, predicting that both light and radio waves are electric and magnetic phenomena. While Faraday had discovered that changes in magnetic fields produce electric fields, Maxwell added the converse: changes in electric fields produce magnetic fields even in the absence of electric currents. Maxwell predicted that electromagnetic disturbances traveling through empty space have electric and magnetic fields at right angles to each other and that both fields are perpendicular to the direction of the wave. He concluded that the waves move at a uniform speed equal to the speed of light and that light is one form of electromagnetic wave. Their elegance notwithstanding, Maxwell's radical ideas were accepted by few outside England until 1886, when the German physicist Heinrich Hertz verified the existence of electromagnetic waves traveling at the speed of light; the waves he discovered are known now as radio waves.
Maxwell's four field equations represent the pinnacle of classical electromagnetic theory. Subsequent developments in the theory have been concerned either with the relationship between electromagnetism and the atomic structure of matter or with the practical and theoretical consequences of Maxwell's equations. His formulation has withstood the revolutions of relativity and quantum mechanics. His equations are appropriate for distances as small as 10−10 centimetres—100 times smaller than the size of an atom. The fusion of electromagnetic theory and quantum theory, known as quantum electrodynamics, is required only for smaller distances.
While the mainstream of theoretical activity concerning electric and magnetic phenomena during the 19th century was devoted to showing how they are interrelated, some scientists made use of them to discover new properties of materials and heat. Weber developed Ampère's suggestion that there are internal circulating currents of molecular size in metals. He explained how a substance loses its magnetic properties when the molecular magnets point in random directions. Under the action of an external force, they may turn to point in the direction of the force; when all point in this direction, the maximum possible degree of magnetization is reached, a phenomenon known as magnetic saturation. In 1895 Pierre Curie of France discovered that a ferromagnetic substance has a specific temperature above which it ceases to be magnetic. Finally, superconductivity was discovered in 1900 by the German physicist Heike Kammerlingh-Onnes. In superconductivity, electric conductors lose all resistance at very low temperatures.
Although little of major importance was added to electromagnetic theory in the 19th century after Maxwell, the discovery of the electron in 1898 opened up an entirely new area of study: the nature of electric charge and of matter itself. The discovery of the electron grew out of studies of electric currents in vacuum tubes. Heinrich Geissler, a glassblower who assisted the German physicist Julius Plücker, improved the vacuum tube in 1854. Four years later, Plücker sealed two electrodes inside the tube, evacuated the air, and forced electric currents between the electrodes; he attributed the green glow that appeared on the wall of the tube to rays emanating from the cathode. From then until the end of the century, the properties of cathode-ray discharges were studied intensively. The work of the English physicist Sir William Crookes in 1879 indicated that the luminescence was a property of the electric current itself. Crookes concluded that the rays were composed of electrified charged particles. In 1898 another English physicist, Sir J.J. Thomson, identified a cathode ray as a stream of negatively charged particles, each having a mass 1/1836 smaller than that of a hydrogen ion. Thomson's discovery established the particulate nature of charge; his particles were later dubbed electrons.
Following the discovery of the electron, electromagnetic theory became an integral part of the theories of the atomic, subatomic, and subnuclear structure of matter. This shift in focus occurred as the result of an impasse between electromagnetic theory and statistical mechanics over attempts to understand radiation from hot bodies. Thermal radiation had been investigated in Germany by the physicist Wilhelm Wien between 1890 and 1900. Wien had virtually exhausted the resources of thermodynamics in dealing with this problem. Two British scientists, Lord Rayleigh (John William Strutt) and Sir James Hopwood Jeans, had by 1900 applied the newly developed science of statistical mechanics to the same problem. They obtained results that, though in agreement with Wien's thermodynamic conclusions (as distinct from his speculative extensions of thermodynamics), only partially agreed with experimental observations. The German physicist Max Planck attempted to combine the statistical approach with a thermodynamic approach. By concentrating on the necessity of fitting together the experimental data, he was led to the formulation of an empirical law that satisfied Wien's thermodynamic criteria and accommodated the experimental data. When Planck interpreted this law in terms of Rayleigh's statistical concepts, he concluded that radiation of frequency ν exists only in quanta of energy. Planck's result, including the introduction of the new universal constant h in 1900, marked the foundation of quantum mechanics and initiated a profound change in physical theory (see atom: Bohr's shell model).
By 1900 it was apparent that Thomson's electrons were a universal constituent of matter and, thus, that matter is essentially electric in nature. As a result, in the early years of the 20th century, many physicists attempted to construct theories of the electromagnetic properties of metals, insulators, and magnetic materials in terms of electrons. In 1909 the Dutch physicist Hendrik Antoon Lorentz succeeded in doing so in The Theory of Electrons and Its Applications to the Phenomena of Light and Radiant Heat; his work has since been modified by quantum theory.
The other major conceptual advance in electromagnetic theory was the special theory of relativity. In Maxwell's time, a mechanistic view of the universe held sway. Sound was interpreted as an undulatory motion of the air, while light and other electromagnetic waves were regarded as undulatory motions of an intangible medium called ether. The question arose as to whether the velocity of light measured by an observer moving relative to ether would be affected by his motion. Albert Abraham Michelson and Edward W. Morley of the United States had demonstrated in 1887 that light in a vacuum on Earth travels at a constant speed which is independent of the direction of the light relative to the direction of Earth's motion through the ether. Lorentz and Henri Poincaré, a French physicist, showed between 1900 and 1904 that the conclusions of Michelson and Morley were consistent with Maxwell's equations. On this basis, Lorentz and Poincaré developed a theory of relativity in which the absolute motion of a body relative to a hypothetical ether is no longer significant. Poincaré named the theory the principle of relativity in a lecture at the St. Louis Exposition in September 1904. Planck gave the first formulation of relativistic dynamics two years later. The most general formulation of the special theory of relativity, however, was put forth by Einstein in 1905, and the theory of relativity is usually associated with his name. Einstein postulated that the speed of light is a constant, independent of the motion of the source of the light, and showed how the Newtonian laws of mechanics would have to be modified. While Maxwell had synthesized electricity and magnetism into one theory, he had regarded them as essentially two interdependent phenomena; Einstein showed that they are two aspects of the same phenomenon.
Maxwell's equations, the special theory of relativity, the discovery of the electronic structure of matter, and the formulation of quantum mechanics all occurred before 1930. The quantum electrodynamics theory, developed between 1945 and 1955, subsequently resolved some minute discrepancies in the calculations of certain atomic properties. For example, the accuracy with which it is now possible to calculate one of the numbers describing the magnetic moment of the electron is comparable to measuring the distance between New York City and Los Angeles to within the thickness of a human hair. As a result, quantum electrodynamics is the most complete and precise theory of any physical phenomenon. The remarkable correspondence between theory and observation makes it unique among human endeavours.
Electromagnetic technology began with Faraday's discovery of induction in 1831 (see above). His demonstration that a changing magnetic field induces an electric current in a nearby circuit showed that mechanical energy can be converted to electric energy. It provided the foundation for electric power generation, leading directly to the invention of the dynamo and the electric motor. Faraday's finding also proved crucial for lighting and heating systems.
The early electric industry was dominated by the problem of generating electricity on a large scale. Within a year of Faraday's discovery, a small hand-turned generator in which a magnet revolved around coils was demonstrated in Paris. In 1833 there appeared an English model that featured the modern arrangement of rotating the coils in the field of a fixed magnet. By 1850 generators were manufactured commercially in several countries. Permanent magnets were used to produce the magnetic field in generators until the principle of the self-excited generator was discovered in 1866. (A self-excited generator has stronger magnetic fields because it uses electromagnets powered by the generator itself.) In 1870 Zénobe Théophile Gramme, a Belgian manufacturer, built the first practical generator capable of producing a continuous current. It was soon found that the magnetic field is more effective if the coil windings are embedded in slots in the rotating iron armature. The slotted armature, still in use today, was invented in 1880 by the Swedish engineer Jonas Wenström. Faraday's 1831 discovery of the principle of the alternating-current (AC) transformer was not put to practical use until the late 1880s when the heated debate over the merits of direct-current and alternating-current systems for power transmission was settled in favour of the latter.
At first, the only serious consideration for electric power was arc lighting, in which a brilliant light is emitted by an electric spark between two electrodes. The arc lamp was too powerful for domestic use, however, and so it was limited to large installations like lighthouses, train stations, and department stores. Commercial development of an incandescent filament lamp, first invented in the 1840s, was delayed until a filament could be made that would heat to incandescence without melting and until a satisfactory vacuum tube could be built. The mercury pump, invented in 1865, provided an adequate vacuum, and a satisfactory carbon filament was developed independently by the English physicist Sir Joseph Wilson Swan and the American inventor Thomas Edison during the late 1870s. By 1880 both had applied for patents for their incandescent lamps, and the ensuing litigation between the two men was resolved by the formation of a joint company in 1883. Thanks to the incandescent lamp, electric lighting became an accepted part of urban life by 1900. The tungsten filament lamp, introduced during the early 1900s, was long the principal form of electric lamp, though it was supplanted by more efficient fluorescent gas discharge lamps and light-emitting diodes (LEDs).
Electricity took on a new importance with the development of the electric motor. This machine, which converts electric energy to mechanical energy, has become an integral component of a wide assortment of devices ranging from kitchen appliances and office equipment to industrial robots and rapid-transit vehicles. Although the principle of the electric motor was devised by Faraday in 1821, no commercially significant unit was produced until 1873. In fact, the first important AC motor, built by the Serbian-American inventor Nikola Tesla, was not demonstrated in the United States until 1888. Tesla began producing his motors in association with the Westinghouse Electric Company a few years after DC motors had been installed in trains in Germany and Ireland. By the end of the 19th century, the electric motor had taken a recognizably modern form. Subsequent improvements have rarely involved radically new ideas. However, the introduction of better designs and new bearing, armature, magnetic, and contact materials has resulted in the manufacture of smaller, cheaper, and more efficient and reliable motors.
The modern communications industry is among the most spectacular products of electricity. Telegraph systems using wires and simple electrochemical or electromechanical receivers proliferated in western Europe and the United States during the 1840s. An operable cable was installed under the English Channel in 1865, and a pair of transatlantic cables were successfully laid a year later. By 1872 almost all of the major cities of the world were linked by telegraph.
Alexander Graham Bell patented the first practical telephone in the United States in 1876, and the first public telephone services were operating within a few years. In 1895 the British physicist Sir Ernest Rutherford advanced Hertz's scientific investigations of radio waves and transmitted radio signals for more than one kilometre. Guglielmo Marconi, an Italian physicist and inventor, established wireless communications across the Atlantic employing radio waves of approximately 300- to 3,000-metre wavelength in 1901. Broadcast radio transmissions were established during the 1920s.
Telephone transmissions by radio waves, the electric recording and reproduction of sound, and television were made possible by the development of the triode tube. This three-electrode tube, invented by the American engineer Lee de Forest, permitted for the first time the amplification of electric signals. Known as the Audion, this device played a pivotal role in the early development of the electronics industry.
The first telephone transmission via radio signals was made from Arlington, Virginia, to the Eiffel Tower in Paris in 1915, and a commercial radio telephone service between New York City and London was begun in 1927. Besides such efforts, most of the major developmental work of this period was tied to the radio and phonograph entertainment industries and the sound film industry. Rapid progress was made toward transmitting moving pictures, especially in Great Britain; just before World War II the British Broadcasting Corporation inaugurated the first public television service. Today many regions of the electromagnetic spectrum are used for communications, including microwaves in the frequency range of approximately 7 × 109 hertz for satellite communication links and infrared light at a frequency of about 3 × 1014 hertz for optical fibre communications systems.
Until 1939 the electronics industry was almost exclusively concerned with communications and broadcast entertainment. Scientists and engineers in Britain, Germany, France, and the United States did initiate research on radar systems capable of aircraft detection and antiaircraft fire control during the 1930s, however, and this marked the beginning of a new direction for electronics. During World War II and after, the electronics industry made strides paralleled only by those of the chemical industry. Television became commonplace, and a broad array of new devices and systems emerged, most notably the electronic digital computer.
The electronic revolution of the last half of the 20th century was made possible in large part by the invention of the transistor (1947) and such subsequent developments as the integrated circuit. (For detailed coverage of these and other major advances, see electronics.) This miniaturization and integration of circuit elements has led to a remarkable diminution in the size and cost of electronic equipment and an equally impressive increase in its reliability.


Hear Susan share her thoughts on ways the legal profession can bridge what some see as fundamental differences in mindset between senior and millennial lawyers in the workplace. Susan's realistic, yet hopeful, message is that bad practice habits, which developed over past eras and have led to toxic environments within the walls of too many law firms and legal institutions, are not beyond repair if we listen to the voices of a new generation of lawyers and help them - and us - find a better way forward.
There will be light appetizers and drinks.


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Rachel Cousins: "Love Language"
Rachel Cousins is changing her tune and expressing herself with "Love Language."
The new song is a departure from her folk and acoustic roots. It's a pop song with an R&B vibe. Cousins' smooth vocals on the track showcase her versatility and provide a sexy, cool tone. "Love Language" proves that she's ready to take on the Pop world.
Throughout her career, the Canadian singer/songwriter has collaborated with many other Newfoundland stars and has received accolades for her musical abilities. Cousins inked a publishing deal and had her songs placed in TV shows and a TV movie.
Last year, two of her songs made East Coast Music List's Top 100, coming in at numbers two and twelve. She recently took home Music NL's Pop Artist Of the Year award. In addition, her producing skills left her a finalist in CBC Music's Toyota Searchlight 2021 competition.
https://soundcloud.com/rcousins12/love-language/s-G7E6JLGP5te

redpajama_set_name: RedPajamaCommonCrawl


Can I get paid for doing community service?
Only students with FEDERAL work-study can be paid for their community service. Students with CIT work-study (usually International students) or students with no work-study at all cannot be paid (they can still volunteer, however). If you are unsure if you have received federal work-study, please check with Financial Aid.
How much to I get paid?
Federal work-study recipients are paid $20.00/hr for their community service work.
Students with federal work-study need to fill out 2 forms with Human Resources: the I-9 and W-4. The I-9 requires three forms of identification (See back of I-9 form). If you have worked at Caltech previously, you may already have an I-9 and W-4 on file.
You will enter your time online every two weeks according to the pay schedule. You can have the check delivered to your designated address or set up direct deposit with Human Resources. You will not be paid until your paperwork (I-9 and W-4) has been completed and processed by Human Resources.
You can chose from the Caltech Y list of Work Study Opportunities.


For many beauty brands, global growth is part of their strategy for success.
The Cosmetics Business Regulatory Summit brings together industry experts to provide updates and guides on entry protocols for key markets and offer valuable knowledge on how to improve strategy and meet compliance in the most efficient and cost effective way.
Visitors will have the opportunity to discover the latest beauty trends and innovations that are transforming the industry, and best practice when it comes to regulation and marketing.


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Vulture Droppings
Home > Movies	> FLOP POP FIZZLE, The Obligatory Weekend B.O. Report: 'Cloudy' Rains Over The Rest Of The New Releases
FLOP POP FIZZLE, The Obligatory Weekend B.O. Report: 'Cloudy' Rains Over The Rest Of The New Releases
September 20th, 2009 admin	Leave a comment Go to comments
Sony's 3D toon-tastic adaptation of the kids classic Cloudy with a Chance of Meatballs trounced the competition, earning $30.1 M for first place at the box office this weekend. No surprise there, as family-friendly releases and 3D have been a surefire combination lately. The real surprise was how poorly the rest of the new movies performed.
The Informant came in a very distant second place with $10.5 M. Neither the reviews praising Matt Damon's portrayal of corporate whistleblower Mark Whitacre, nor the ads, selling it as a tongue-in-cheek comedy/satire (which may have been confusing considering the serious subject matter), were enough to entice viewers. It's yet another financial disappointment for Steven Soderbergh, who's had a rough summer at the box office.
The low opening certainly won't help his relationship with the major studios, which has been on shaky ground since Sony cancelled his baseball epic Moneyball less than three days before production was set to begin in June. In an interview that appeared in The New Yorker, Soderbergh said,
Basically, right now the film industry is becoming more and more timid and even overcautious. I know, it's pretty hard to understand. They're afraid. Afraid of me, of my ideas and of my vision of history."
Tyler Perry's I Can Do Bad All By Myself dropped more than 50% in its second week, going from first to third place, with a new cume of $37.9 M. The Jennifer Aniston rom-com Love Happens, which received extremely negative reviews, (even for an Aniston movie) debuted in fourth place.
Despite the promise of girl-on-girl action and an up close and personal view of a sex symbol, Megan Fox fans of the young male variety (or any variety, for that matter) steered clear of her first starring vehicle, the aptly titled Jennifer's Body. The Diablo Cody-penned vampire thriller, earned a paltry $6.8 M for fifth place, prompting Nikke Finke to question whether Cody is, "filmdom's one-hit wonder".
The rest of the list consists of hold-overs from last week. The animated kids pic 9 didn't fare well against competition from Cloudy, falling to sixth place with $5.6 M. Quentin Tarantino's Inglourious Basterds , which has long since reached hit status having already surpassed the $100 M threshold, continued its slow and steady decline, falling to seventh place.
All About Steve won't be another blockbuster for Sandra Bullock. In its third week of release it's already dropped to eighth place with a cume of $26.7 M. And rounding out the top ten, Sorority Row took ninth and The Final Destination, which debuted in first place just three weeks ago, appears to have run out of steam, dropping to tenth place.
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The Straight Dope: The 61st Primetime Emmy Awards The Beatles Rock Band Commercial = Extremely Creepy
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Aloha to the Longest Ad Campaign Ever
Howard Stern Blasts Alejandro González Iñárritu
'Through The Looking Glass' Trailer Stays On Trend
Denise Matthews' Life As Vanity: Sex, Drugs & Salvation
Slow Songs (Say So Much): Advertising Trends At the Movies


Only at The Washington Times: Tim Lemke discusses the business of sports.
In which a lot of people get thanked.
Cites "circumstances of last two weeks."
Forbes says the Wizards are worth $313 million, ranking them 19th in the NBA.
Gammons, like others, recognized MLB Network as a less frenetic place to work.
A conversation with Sam Cooper, head of EA Sports FIFA franchise.
Maury Brown of the Business of Sports Network and I engage in a long email conversation about the top issues of the day.
Fans in parts of Maryland will miss out on seeing some games this year.
World Cup soccer? It's a possibility.
Why Does NBA's Broadband Product Cost So Much?
If you want to watch out-of-market NBA games on your computer, you have to pay $150. That's $40 more than baseball's similar service. Why the disparity in price?
Former Anheuser-Busch sports marketer now involved in production of play about the life of Vince Lombardi.
New list of possible "winners" and "losers."


This large starfish gets its name from the rows of spines running down each arm. It is a hungry predator of molluscs, sea urchins, other starfish, dead fish and just about anything that crosses its path on the sea bed. It moves relatively quickly on its tube feet when hunting down prey which it detects by smell. Like other starfish if it loses an arm, it can grow another one to replace it!


With over 3.5 billion monthly video views, Dailymotion is definitely a great platform to promote brands. Don't miss the chance to promote your video and your brand with our professional services.
Buy Dailymotion Views for your Video and make you look more popular, improve your reputation, increase your engagement and attracting new followers.


Discussion in 'Arts and Entertainment' started by BryanMaloney, Mar 9, 2012.
My wife is watching The Help, and she is astonished at terms like "the colored situation". I reminded her that she and I (45 years old) are only one generation from such attitudes being quite widespread and commonly acceptable.


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Orb Weavers
Cobweb Spiders
Huntsman Spiders
Wolf Spiders
Sicariidae Spiders
Funnel Weaver Spiders
Crab Spiders
Nursery Web Spiders
Spiders in US
Spider Facts
Parts of a Spider
Life Cycle of a Spider
Where do Spiders Live
What do Spiders Eat
How long do Spiders Live
Where do Spiders go in Winter
Spider Ballooning
Spider Molting
Spider Eyes
Spider Predators
Home / Sicariidae Spiders / Brown Recluse (Loxosceles reclusa)
Brown Recluse (Loxosceles reclusa)
The brown recluse spider, belonging to the Sicariidae family is one among the three species in North America, besides the Chilean recluse and black widow, known for their medically significant venom. Indigenous to most parts of America, it is mainly spotted in the central and southern parts of the U.S.
Physical Description &Identification
Size: They are 6-20 mm (0.24 -0.79 inches) in size, though they can be larger.
Family: Sicariidae
Genus: Loxosceles
Scientific name: Loxosceles reclusa
Color: As its name suggests, it has a light brown body with blackish-gray, whitish, or dark brown tinges. Its cephalothorax, on the other hand, maybe yellowish-brown or light brown.
Other characteristics: The dorsal section of the brown recluse's cephalothorax contains markings and a black line, forming a violin-like pattern lying pointed towards the abdomen. Unlike most other spiders, the brown recluse has six eyes (one medial, two lateral pairs).
Brown Recluse Size
The silken egg sacs, off-white in color with a diameter of 1/3 inch contains about 50 eggs on an average.
Brown Recluse Egg Sac
Spiderlings
The spiderlings of this species come out of the egg case in about 36 days, taking a year to mature. The immature ones look similar to the adults though they have a light brown body. Moreover, by the time they are juveniles, this species attain mobility and can travel for long distances. Even the spiderlings can inject venom that could cause serious reactions in mankind.
Baby Brown Recluse
Their webs are irregular and loosely constructed mostly found in dark, dingy areas. However, being hunting spiders, they generally do not take the help of their web for capturing preys.
Brown Recluse Spider Web
Is the Brown Recluse Spider Poisonous and Does It Bite
As mentioned above, the brown recluse spider (males, females as well as juveniles) is potentially dangerous since it possesses a hemotoxic venom that could require medical attention. The symptoms of the bite could vary from mild, moderate to severe. In fact, in most cases, the bites are without necrosis, with the effect being not more than a bee sting. However, there have been exceptions where the bites have produced severe impact resulting in dermonecrotic lesions.
Having mentioned about the severity of its bite, it is still essential to say that these species are not aggressive and would bite only when provoked or disturbed. Many victims have reported being attacked by the brown recluse while attempting to wear clothes or shoes left untouched for many years.
There have been rare cases about death from this spider and children below seven as well as those having a weak immune system are more susceptible to fatalities.
Brown Recluse Image
What are the Symptoms of a Brown Recluse Spider Bite
The symptoms could be mild to severe, depending on the intensity of the bite. In majority cases, the pain and itchiness are experienced between 2 and 8 hours from being bitten and in case of extremities, the situation may worsen within a day or two.
Common symptoms include redness, itching, and pain in the area of the bite, alongside a deep sore. Fever, weakness, chills, nausea and joint pains could even occur and in rare cases, there may be seizures and under severe circumstances, the person may even go into a coma.
The treatment depends on the extremities of the symptoms and may vary from one person to the other. Some of the common treatments undertaken by medical personals include pain medication, tetanus immunization, antibiotics, and even antihistamines.
Brown Recluse Spider Picture
Lifespan 1 to 2 years
Distribution The south-central and Midwestern parts of the United States including areas of southeastern Nebraska, Illinois, Ohio, Indiana, western Georgia and northern parts of Kentucky
Habitat Dry, dark, and dingy areas, alongside nesting places which are undisturbed like sheds, woodpiles, garages, and closets
Common Predators Birds, cats wasps and other spider species like cat-faced, wolf and crab
Diet Soft-bodied insects like cockroaches, flies, crickets, and moths
The violin pattern on their body has earned them the nicknames violin, fiddle back, and brown fiddler.
Another spider of notorious reputation is the hobo spider which is also reddish-brown but different from the brown recluse in appearance, as the former has a distinct pattern on its abdomen not present in the latter.
Image Credits: Canr.msu.edu, Resize.hswstatic.com, Pestworld.org, I.ytimg.com, Bioweb.uwlax.edu, Brown-recluse-spiders.net, Ask.extension.org
By Mumpi Ghosh | Updated : September 13, 2019
Other Spiders in this Family
Hexophthalma
Six-eyed Sand (Hexophthalma hahni)
Recluse(Loxosceles)
Mediterranean Recluse (Loxosceles rufescens)
Texas Recluse (Loxosceles devia)
© 2022 (Spider Identifications). All rights reserved. Reproduction in whole or in part without permission is prohibited.


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Q: Throttle a detail view in django rest framework I have a custom throttle:
from rest_framework.throttling import UserRateThrottle

class OncePerDayUserThrottle(UserRateThrottle):
   rate = '1/day'

I use this throttle in a class api view as such:
class PostHitCount(APIView):
   throttle_classes = [OncePerDayUserThrottle]

   def post(self, request, hitcount_pk, format=None):
       # my post method

The url corresponding to this view is
path('add-hitcount/<int:hitcount_pk>/', PostHitCount.as_view())

If i access this view for the first time via url add-count/1/, i am permitted.
If i later post to the same url, i am not permitted (which is ok!).
Now if i post to the url add-count/2/, the request is rejected since the user already accessed that view!
How can i permit requests with another detail url?
Also, is it possible to set the throttle rate to say 1/year or even 1/lifetime ? How ?

A: The best way to do this is to override the "get_cache_key" method.
from rest_framework.throttling import UserRateThrottle

class OncePerDayUserThrottle(UserRateThrottle):
    rate = '1/day'
    cache_format = 'throttle_%(scope)s_%(ident)s_%(detail)s'

    def get_cache_key(self, request, view):
        """
        Limits the rate of API calls that may be made by a given user.

        The user id will be used as a unique cache key if the user is
        authenticated.  For anonymous requests, the IP address of the request will
        be used.
        """
        scope = 'user'

        def get_cache_key(self, request, view):
            if request.user.is_authenticated:
                ident = request.user.pk
            else:
                ident = self.get_ident(request)

            return self.cache_format % {
                'scope': self.scope,
                'ident': ident,
                'detail': view.kwargs.get("hitcount_pk")
            }

A: Did you see this?
https://www.django-rest-framework.org/api-guide/throttling/#userratethrottle
You need to use a "scope":
class BurstRateThrottle(UserRateThrottle):
    scope = 'burst'

class SustainedRateThrottle(UserRateThrottle):
    scope = 'sustained'

And define the scope in settings.py:
REST_FRAMEWORK = {
    'DEFAULT_THROTTLE_CLASSES': [
        'example.throttles.BurstRateThrottle',
        'example.throttles.SustainedRateThrottle'
    ],
    'DEFAULT_THROTTLE_RATES': {
        'burst': '60/min',
        'sustained': '1000/day'
    }
}

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Global Warming happening yet?
Our business friendly mates on the right don't like Global warming. They would hate to admit that what those tree huggers have been pointing out for years is actually true and that the capitalist consumer culture they love so much might in fact be killing off the planet. Indeed I've even had right wing bloggers here on this site claim environmental concerns aren't just the preserve of the left, and that they care as well. Neato. The fact still remains that our right wing friends and the systems they have created to benefit themselves have a lot to answer for the current environmental problems we face, should they have a role in the changes or should they simply have the changes forced upon them? As the environmental consequences of rampant capitalist consumerisim become more and more apparent, these are questions that Australia is being forced to ask itself now.
Australia ponders climate future
Parts of Australia are in the grip of the worst drought in memory.
Rainfall in many eastern and southern regions has been at near record lows. On top of that, the weather has been exceptionally warm. The parched conditions have sparked an emotional debate about global warming. Conservationists insist the "big dry" is almost certainly the result of climate change and warn that Australia is on the brink of environmental disaster.
Other experts believe such hysteria is wildly misplaced and that the country shouldn't panic.
'A war-like scenario'
The drought in Australia has lasted for more than five years. The worry for some is that this could be the start of a protracted period of low rainfall that could go on for decades. "The really scary thing is last time we had a drought of this intensity that lasted about five years - it lasted for about 50 years," cautioned Professor Andy Pitman from Macquarie University in Sydney. "The politicians truly believe this is a five-year or six-year drought that will break sometime in 2007 or 2008. But it might not break until 2050 and we aren't thinking in those terms at this stage," Professor Pitman told the BBC. Global warming, the drought and the future of dwindling water supplies will undoubtedly dominate talk at barbeques and dinner parties this festive season in Australia. "We're in a state of emergency," said Cate Faehrmann from the Nature Conservation Council of New South Wales. "We need to treat this as a war-like scenario. The people are really worried that we are going to run out of water." She added: "I can imagine Australia being a desert in a few decades' time in some of these agricultural areas. The soil is blowing away, the rivers are drying up. "I think there will be plots of land abandoned and perhaps whole agricultural practices abandoned."
At 30/12/06 12:48 am, Bomber said...
Hey has anyone else noticed that only on Rupert Murdoch's news channels that they are reporting that 'climate scientists' (they won't say who) are saying that it's all very natural for Australia to be going through this drought 'there are natural cycles' they say - here's the deal folks, yes there are natural cycles, but global warming means that freak 'once every 40 year' weather events will happen EVERY YEAR - it's not that we haven't had snow falling in Summer in NZ ever before, but it is a freak occurance which will now start becoming the norm. Oh and here's something to think about - let's remember that we are living with temperatures .6 degrees above where they used to be, because every Government on the face of the planet are a pack of weak corporate whores, we are allowing the planet to warm another1.4 degrees to 2 degrees in order to allow as little interference to profit margins as possible. Imagine how fucked the planet is going to get at 2 degrees when we can see the damage of .6 degrees.....
At 1/1/07 3:28 pm, SamClemenz said...
Climate change isn't happening is a favorite slogan for Corporatist denyer's with profit forecasts in mind for this century. Uh - Charlie Peddersen, I hope you are reading this. Try marketing this strategy to your share holder's!
Article from Common Dreams.org 31/12/06
The End of the West as We Know It?
by Anatol Lieven
Every political, social and economic system ever created has sooner or later encountered a challenge that its very nature has made it incapable of meeting. The Confucian ruling system of imperial China, which lasted for more than 2,000 years, has some claim still to be the most successful in history, but because it was founded on values of stability and continuity, rather than dynamism and inventiveness, it eventually proved unable to survive in the face of Western imperial capitalism.
For market economies, and the Western model of democracy with which they have been associated, the existential challenge for the foreseeable future will be global warming. Other threats like terrorism may well be damaging, but no other conceivable threat or combination of threats can possibly destroy our entire system. As the recent British official commission chaired by Sir Nicholas Stern correctly stated, climate change "is the greatest and widest-ranging market failure ever seen."
The question now facing us is whether global capitalism and Western democracy can follow the Stern report's recommendations, and make the limited economic adjustments necessary to keep global warming within bounds that will allow us to preserve our system in a recognizable form; or whether our system is so dependent on unlimited consumption that it is by its nature incapable of demanding even small sacrifices from its present elites and populations.
If the latter proves the case, and the world suffers radically destructive climate change, then we must recognize that everything that the West now stands for will be rejected by future generations. The entire democratic capitalist system will be seen to have failed utterly as a model for humanity and as a custodian of essential human interests.
Even the relatively conservative predictions offered by the Stern report, of a drop in annual global gross domestic product of up to 20 percent by the end of this century, imply a crisis on the scale of the Great Depression of the 1930s; and as we know, the effects of that depression were not restricted to economics. In much of Europe, as well as Latin America and Japan, democracies collapsed and were replaced by authoritarian regimes.
As the report makes clear, however, if we continue with "business as usual" when it comes to the emission of greenhouse gases, then we will not have to wait till the end of the century to see disastrous consequences. Long before then, a combination of floods, droughts and famine will have destroyed states in many poorer parts of the earth — as has already occurred in recent decades in Somalia. (I might jump in for a moment and mention the situation that is currently going on in Australia for added reinforcements)
If the conservative estimates of the Stern report are correct, then already by 2050 the effects of climate change may be such as to wreck the societies of Pakistan and Bangladesh; and if these states collapse, how can India and other countries possibly insulate themselves?
At that point, not only will today's obsessive concern with terrorism appear insignificant, but all the democratizing efforts of Western states, and of private individuals and bodies like George Soros (Google him for info on his "Open Society") and his Open Society Institute, will be rendered completely meaningless. So, of course, will every effort directed today toward the reduction of poverty and disease.
And this is only to examine the likely medium-term consequences of climate change. For the further future, the report predicts that if we continue with business as usual, then the rise in average global temperature could well top 5 degrees Celsius. To judge by what we know of the history of the world's climate, this would almost certainly lead to the melting of the polar ice caps, and a rise in sea levels of up to 25 meters.
As pointed out by Al Gore in "An Inconvenient Truth," this would mean the end of many of the world's greatest cities. The resulting human migration could be on such a scale as to bring modern civilization to an end.
If this comes to pass, what will our descendants make of a political and media culture that devotes little attention to this threat when compared with sports, consumer goods, leisure and a threat from terrorism that is puny by comparison? Will they remember us as great paragons of human progress and freedom? They are more likely to spit on our graves.
Underlying Western free-market democracy, and its American form in particular, is the belief that this system is of permanent value to mankind: a "New Order of the Ages," as the motto on the U.S. Great Seal has it. It is not supposed to serve only the short- term and selfish interests of existing Western populations. If our system is indeed no more than that, then it will pass from history even more utterly than Confucian China — and will deserve to do so.
At 1/1/07 8:47 pm, Bomber said...
My God that is a powerful essay - thanks for posting it bro - I had never thought about the ramifications for the "self-evident" democratic state, but Anatol Lieven makes a compelling case to suggest the cataclysmic global warming future we face will be populated by people who will look for someone to blame, and of course it will be the secular democratic state that will be attacked for bringing down the wrath of the gods through their own greed. The story of a civilizations collapse through their own greed is a deeply embedded human theme perhaps started as firsthand warnings of such folly and over the centuries have watered down as a suburban myth from history desperately trying to reach out across the eons to warn of oblivion if the path of arrogance is championed as National interest. We ignore these fables at our own peril.


Khaama Press: The Afghanistan Independent Human Rights Commission (AIHRC) Chief Sima Samar has warned Pakistan will be hit by problems it causes in Afghanistan. Samar is in India to participate in an international conference on child and youth. "I believe that our neighbour (Pakistan) should realise that problems that it is causing in Afghanistan is not going to stay within our boundaries. It would reach them," she told IANS in an interview. She also added "As soon as they realise this and take action against enemies of human rights, the world will have a positive change." Click here to read more (external link).
What this crazy woman is talking about ?
She does not listen to the news of massacres inside Pakistan.That country is also in a state of chaos.
These kind of stupid people are running Afghanistan- can you believe that ?????
Free salary with high prestigious government job- but no brain !
A woman is used for publicity and propaganda.