GAS LIGHTING AND THE SAFETY LAMP
William Murdoch lights his House—He brings Gas to London— Sir Humphry Davy and the Safety Lamp.
WILLIAM MURDOCH, whom I have already mentioned as one of the first inventors of a steam engine for traveling on the roads, is best known as the inventor of lighting by coal gas. Murdoch was a born inventor, a tremendous worker, and—fortunately for himself—a very strong man. When he first went to Cornwall for the firm of Boulton and Watt the ignorant miners hated steam engines, and one day, soon after his arrival in Cornwall, four or five strapping mine captains (overseers) came into his engine room at Chacewath and began to sneer at and bully him.
Murdoch flung off his coat, rolled up his sleeves, and said to the biggest of the men, "I’ll take you first." He hammered him properly, and the rest looked on. When the fight was over and the Cornishman lay flat on the floor they merely grinned. "Thou be’est a proper man", said one; and after that not only did the bullying cease, but Murdoch became immensely popular.
Murdoch worked all day and often most of the night on his firm’s engines. When anything went wrong it was always he who was sent for posthaste to do the repairs, and how he found time for his inventions is something of a miracle. in 1791 he took out a patent for a sort of paint to prevent ships’ bottoms from being fouled by weed and shellfish, and about the same time patented a pneumatic lift which was to be worked by compressed air. He also invented a cast-iron cement made of iron and sal ammoniac. He used compressed air to ring the bells in his house, and when the great novelist Sir Walter Scott saw them he insisted upon having all his bells at Abbotsford fitted up in similar fashion.
Murdoch was always devising little "dodges" for his own house, and it was from such a small invention that the discovery of how to utilize coal gas came about.
Years before his time it had been noticed that jets of natural gas were found in coal mines. A writer in Philosopilical Transactions somewhere about the year 1733 speaks of an experiment made in sinking a pit near Whitehaven. A bladder was filled with gas from one of these natural jets, tied up, and left for some days. Then the contents, pressed gently through a small jet, were directed into the flame of a candle and found to burn with a strong flame. Six years later Dr. John Clayton actually manufactured this gas—"spirit of coal", he called it—from coal placed in a small retort. Other similar experiments were made in 1767 and 1784, but only as a sort of scientific amusement, and it was not until Murdoch’s time that it occurred to any one to make real use of coal gas.
In those days inventors usually worked behind locked doors; indeed, many of them do so still, and one day Murdoch was very busy in his closed workshop at Camborne in company with his friend Dr. Boaze. Half a dozen boys who were keen to find out what was going on were hanging about outside when suddenly the door opened and Murdoch himself came out. He laid a perfectly friendly hand on the shoulder of the nearest boy, whose name was William Symons. "Run down to the shop, Bill," he said, "and get me a thimble."
Symons was off like a shot, but when he came back with the thimble he pretended to have lost it. While he searched in his pocket he took the opportunity of slipping in at the door, and there he stood watching with eager eyes. On the fire was a heavy kettle filled with coal, to the spout of which was attached a tube. When Symons at last produced the thimble, Murdoch bored a small hole in it and then fastened it to the end of the tube. Then he applied a light to the thimble, and a long jet of burning gas rushed out.
In 1792 Murdoch fitted up a retort in his house, piped the place, and lighted every room with coal gas. He also made himself a gas lantern with a container for the gas, and used this when he walked across the moors at night.
Other people were experimenting with coal gas, and in 1801 it was proposed to light the streets of Paris in this manner. The only objection was that no one in Paris knew quite how to do it. Murdoch, however, was at work, and in 1802 he illuminated the front of Boulton and Watt’s works in Soho with gas. People came from all parts of London to stare at the new illumination, for at that date, little more than a century ago, the dirty, narrow streets were lighted only with occasional dingy oil lamps or with flaring, smoky torches. Linkboys, as they were called, always accompanied wealthy folk when going out to any evening entertainment.
Boulton and Watt built new plants for making gas retorts and pipes, and began to fit up many of the big cotton mills in the North with the new light. Yet the people at large did not take to it. Even so great a man as Sir Humphry Davy, inventor of the safety lamp, laughed at gas lighting, and asked Murdoch if he meant to make the dome of St. Paul’s into a gasometer. Another well-known professor declared that they might as well light London "with a slice of the moon."
Murdoch, however, went steadily on with his work, and in 1808 read a paper before the Royal Society. Modest as he was, he did say this much:
"I believe I may claim both the first idea of applying and the first application of this gas to economical purposes." The Society awarded him their Gold Medal for his work.
Clegg, a pupil of Murdoch’s, joined the Gas Company, and did good work, and in 1814 Westminster Bridge was lighted with gas. Crowds used to follow the lamplighter every evening on his rounds. Then the old oil lamplighters struck, and Mr. Clegg had to go round and light the lamps himself.
Murdoch had never taken out a patent for his invention, and so failed to gain the fortune which should have been his due; but he had a good salary from Boulton and Watt, and he and Watt were firm friends. He went on inventing, and among other things discovered a substitute for isinglass, and went up to London to show this to various brewers. He had fine rooms in London, but treated them just as he did his own workshops. Imagine the horror of his landlady when, coming into his sitting room one morning, she found the handsomely papered walls all covered with wet fish skins hung out to dry! At the moment Murdoch was actually pinning up a big cod skin. She turned him out instantly, much to the inventor’s dismay.
In 1815 Murdoch was busy fitting up an apparatus for heating the water in the baths at Leamington when a heavy mass of cast iron fell upon him, breaking his leg and leaving him very lame. But he recovered his health, and lived until 1839, dying at the good old age of eighty-five.
I mentioned Sir Humphry Davy as having been foolish enough to jeer at Murdoch’s system of gas lighting. But even the wisest of us make mistakes, and so great is our debt to Sir Humphry that we can well afford to forgive him for this one blunder.
Humphry Davy was born at Penzance in Cornwall in the year 1778, and was a very good-looking, taking sort of boy. He went to school at Truro, and developed a taste for chemistry. In those days very few people knew anything about chemistry, and there were but few books on the subject. Young Humphry made friends with an interesting man called Dunkin, who was a saddler by trade, but deeply interested in nature and science. When Humphry was seventeen he was apprenticed to a surgeon-apothecary in Penzance, and this gave him a chance to indulge in chemical experiments. He wrote verses, he studied all kinds of books, and in his spare time he went fishing.
When he was nineteen he fell in with Dr. Thomas Beddoes of Clifton, who had been a reader in chemistry at Oxford and was well known for his writings. One of Beddoes’ books, "The History of Isaac Jenkins", which laid down in a popular style rules of health for poor people, had the enormous sale of forty thousand copies. He had married Anna, sister of the celebrated Maria Edgeworth, and was a friend of Thomas Wedgwood of pottery fame. He opened a "pneumatic" hospital at Clifton, where he cured his patients by making them breathe medicated air.
It was of this hospital that young Humphry Davy soon became superintendent, and here the young man met many celebrated people, including the poets Southey and Coleridge and the Earl of Durham. He began experiments with gases, and more than once nearly killed himself by breathing poisonous mixtures. He discovered nitrous oxide, or laughing gas, and in 1799 published "Researches, Chemical and Philosophical", a book which made him a great reputation and led to his appointment, at the age of only twenty-two, as lecturer to the Royal Institute in London.
He was very good-looking, he had fine manners, he dressed well, had a delightful smile and a most taking manner. His lecture room was always crowded, and for two hours on end he could hold his audience in delighted silence. He was the most popular young man in London, yet was never spoiled; his laboratory was the best equipped in London, which, however, takes nothing from the credit of his splendid discoveries. He began by electrolyzing water; then he discovered the two metals potassium and sodium. This he did by means of electricity, and when the little balls of shining molten metal appeared he was so delighted that he shouted and danced around the room.
These were discoveries, but Davy went on to make inventions. It was he who produced the first electric light the world had ever seen. This he did with a battery of two thousand cells paid for by his admirers. I could fill this book with the story of the brilliant young chemist’s numerous discoveries, among which were the elements barium, strontium, calcium, and magnesium. He also did great things for the farmer by his work in agricultural chemistry. In 1812 he received the honor of knighthood, and also was married.
In the year 1815 came the invention for which Davy’s name will always be remembered—that of the safety lamp for collieries. The dreadful explosions which were formerly so common in coal mines and which still occur at times are caused by methane or marsh gas (called by miners "fire damp") leaking out of the coal seams. Mixed with air in the proportion of one part of fire damp to ten of air, methane becomes highly explosive, and the danger is made worse by the fine coal dust suspended in the mine.
Before Davy’s invention, several attempts had been made to construct a safety lantern. Dr. Clanny of Sunderland made one, but it was unfit for ordinary use; George Stephenson invented one that was rather better and was used a good deal under the name of the "Geordie." But Sir Humphry Davy was the first to apply scientific knowledge to the problem, and he discovered that gauze of a certain degree of fineness placed round a flame arrests the passage of that flame to an explosive. He laid down that the apertures in the gauze must not be more than one twenty-second of an inch in diameter, and that the wire itself should be from one fortieth to one sixtieth of an inch in thickness. When a lamp so protected is brought to a part of the pit which is dangerous the flame enlarges and turns pale. This gives warning of the presence of gas, and the miner can either put his lamp out by plunging it in a bucket of water or hurry away to a safer place.
For his work on this lamp Sir Humphry was presented with a testimonial of fifteen hundred pounds and a service of plate. He was also created a baronet. In 1825 he fell ill from a paralytic attack. He went abroad to try to get well, but died in Geneva in 1829. The Swiss gave him a magnificent public funeral. There is a tablet to his memory in Westminster Abbey and a statue in Penzance. Of him it was said after his death: "He was not only one of the greatest but also one of the most amiable and benevolent of men."
One of the most recent of safety lamps is the electric lamp invented by Mr. Edison shortly before the War. It is carried by the miner as an attachment to the front of his cap, and the case in which the battery is carried is secured by a belt to his back. It is impossible for the miner to cause a spark by tampering with the connection; the lamp is handed to him fully charged and with the steel battery case padlocked and proof against rough handling. For this invention Mr. Edison received the Rathenau medal—the greatest honor at the disposal of the American Museum of Safety.