How Do They Work?
A grain elevator is an awesome structure yet it seems simplistic. At first glance you are presented with a large concrete structure that resembles several farm silos strung together. Beyond the huge "towers" that are attached to one side of the elevator, and the fact that these "towers" ride on rails, there doesn't seem to be anything really complicated about the operation of an elevator. However, looks can be deceiving.
After a freighter is tied up alongside an elevator, the elevator's "marine leg", is lowered. The marine leg is a long, massive steel column which houses an endless chain with many buckets attached. The "leg" is dipped into a hold and the buckets bite into the grain and carry it to the top of the elevator (ranging in height from 70 to 140 feet).
When a ship's hold is full, a marine leg can carry grain to an elevator's top at the rate of 35,000 to 40,000 bushels an hour, but as the hold empties and the grain has to be fed to the leg by scoopers, this rapid rate is cut down to around 20,000 bushels an hour. Thus, a "fast house" with two marine legs can unload a 400,000 bushel freighter in ten hours.
When the grain reaches the top of the marine leg, it is dropped into a scale for its first weighing. These scales can weigh about 25 tons of grain at a time. After the weigh-in, the grain is boosted from the top of the marine leg to the top of the elevator proper, carried over the tops of the round bins which lie next to each other, and finally dropped into the assigned bins, according to the grade of the grain.
When grain is taken out of the mammoth bins, it is dropped from the bottom of the bin onto a huge scale and then elevated again to the top of the bins. From the top, it is dropped by gravity through long tubes into waiting barges and box cars. Large elevators can load more than one box car at a time. One elevator, for instance, has four spouts or outgoing legs which can load six 2,000 bushel box cars an hour.
As early as 1905 some marine legs in Buffalo elevators used the "pneumatic principle", a system of air flowing through a tube that sucked up grain like a giant vacuum sweeper. At first, bins were built of wood and usually lined with iron. After 1890 steel bins were built in a number of different arrangements. Since that time reinforced concrete has been used. Round bins were the most common shape though some were rectangular or shaped like a four-pointed star.
As mentioned earlier, some grain elevators in the Buffalo area were called "fast houses" by those who worked there, or stored grain there. Actually, the term "house" refers to the elevators workhouse situated at the top of the structure -- perhaps 250 feet or more above ground. The workhouse had room for lofter legs, shipping scales, cleaning and shipping equipment.
How Were They Built?
Building a grain elevator either of wood or concrete required special skills in engineering and design. One bushel of wheat weighs roughly 60 pounds,so a 1,000,000 bushel capacity elevator contains about 30,000 tons of grain. This creates an average load on the foundation of about 10,000 pounds per square foot. Interesting of note is the fact that the land along the Buffalo River was marsh land with a low load-bearing capacity. So the elevators built before the 1920s had timber pilings driven down into the rock to help support the structure. Oftentimes, these pilings would have to be driven anywhere from 15 to 80 feet below ground level.
If an elevator was located further inland, soil conditions were much better for supporting a heavy structure. Also, steel and concrete came into their own as construction materials. For example, the Agway Elevator was built on a concrete mat 3 feet thick which in turn rests on a natural foundation of stiff clay.
But whatever the foundation for the elevator was, be it wood pilings or concrete slabs, construction of the elevator itself could begin once the base was completed. In 1907, the American Elevator was built of reinforced concrete, a method of taking steel rods and embedding them in the concrete to provide the reinforcement. This method was used to keep the bins from bursting open due to the outward pressure of the grain while at the same time directing the massive load of the grain down to the foundation. And obviously, concrete is fireproof.
Using this method it took about 10 days for the Standard Elevator to reach the height of 125 feet, which was the average height of most bins. After the bins were complete, the workhouse was slipformed up until the elevator reached a height of 200 feet. Because of its complicated design, the workhouse was often built of steel rather than reinforced concrete.
The top deck of a grain elevator under construction was a very busy place. Placement of steel rods, pouring of concrete, and jacking of the form were continuous processes. Generally, each jack man had twelve jacks to tend to. A whistle sounded as the signal for each man to make one turn on each jack. Raising the form six inches required 288 turns -- almost five a minute -- on his jack. Understandably a jack man occasionally got tired enough to miss a few turns causing his section of the form to be lower than the rest, resulting in considerable stress on the form. For obvious reasons, this was not looked upon favorably by the job superintendent.
According to legend, a great deal of steel ended up in the Buffalo River to cover up omissions or weaknesses in construction. Even if this were true, bin burstings were uncommon. Fires, explosions, and collapses for other reasons occasionally occurred, however, and these provided some of the most dramatic events in the history of the Buffalo grain industry.
When Things Went Wrong
Fire destroyed a number of the early wooden elevators in Buffalo. Newspapers related the story when the National and Globe Elevator on the Evans Ship Canal burned to the ground on October of 1963. The National and Globe had been built one hundred years earlier and was abandoned at the time it burned.
After the 1890s, construction with steel and reinforced concrete reduced the problem of fire, except in the grain itself. Spontaneous combustion of grain caused a slow, smoldering fire deep in the interior of a bin. Using water to douse the fire would spoil the unburned grain, so other methods were developed to deal with this problem. The bin may be "turned over;" that is, the grain run out to another bin to cool it off or dry ice can be placed on top. This generated heavy carbon dioxide gas that sank into the grain and smothered the fire below.
Agway "B", one of the first elevators to be constructed of concrete in Buffalo, had topless bins like some of the older wooden elevators. However, topless bins proved to be unsuccessful at preventing fires and explosions. Fires would spread from one bin to another and if an explosion occurred it would cause a chain reaction with the dust from the other bins. There was also the ever-present danger of men falling into the bins.
Agway "A" and Eastern States were built later on using concrete covers for each of the bins. The theory was that if an explosion occurred, the cover would blow off without disturbing the other bins, much like a safety valve protects a steam boiler. The only problem was the fact that these concrete covers were twenty feet in diameter and weighed 4 tons. What would happen if one of the covers were blown into the air and landed in an area where men were working? Obviously not a pretty thought. Luckily, an accident such as that never happened.
Some of the photographs contained on this page were from
The Library of Congress, Detroit Publishing Company Collection,
The Library of Congress, Panaramic Photographs Collection,
The Buffalo and Erie County Historical Society,
The Western New York Heritage Institute and
Lower Lakes Marine Historical Society.
Additional photographs were from the book "Buffalo's Waterfront", another volume of Arcadia Publishing's "Images of America" series; written by Thomas E. Leary and Elizabeth Sholes. This book is available at most bookstores in the Western New York area, or through the Buffalo and Erie County Historical Society.
** Portions of this section were reproduced from the book "Grain Elevators" by Henry H. Baxter; Volume 26 in the "Adventures in Western New York History" series, published by the Buffalo and Erie County Historical Society.