Oliver Evans


A preview to automation

Americans are restless people. They like to move around. They are always looking for new places and new ways of doing things.
In colonial times, this "moving spirit" was a necessity. The soil in the granite area of New England had never been rich. Southern planters
had made their poor lands by over-planting tobacco. Early frontiersmen, who were the first to go out to the North-West territory,
reported that the land around the Ohio River was rich and fertile. For these reason, long before the Revolutionary war, there was a
constant stream of people traveling down the Ohio River from Pittsburgh. We refer to them as "Pioneers" because they were among
the first people to go westward in the development of the United States. Whole families, with their livestock, could be seen on the
crude arks that carried them down the river to new homes in the West. Others too poor to pay for passage by boat, took to the
rough roads and walked hundreds of miles on foot. As they walked, they pushed wheelbarrows and pulled hardcarts that held
their simple agricultural tools and their new household possessions.

Land was cheap and plentiful in the Northwest territory. Before the constitution united the different states into one country, this
territory was claimed by Massachusetts, Virginia, and Connecticut as part of their land under the original chapter. After the country
became the United States, a law was passed to allowed a settler to buy tracts of land in vacant territory by making a down payment
of fifty cents on acre. The balance of one dollard and fifty cents an acre could be paid over a period of four years. By 1800, over a
million Americans were living on the land between the Appalachian Mountains and the Mississippi River.

Cut off from the East by the mountains, the people who settled in this area developed their own trade. They hunted for-bearing
animals, planted grain and raised livestock. Their trading port was New Orleans. But, in the days before the steamboat, the traffic
on the river was only one way. Their flat boats could go down the river, but without power, could not go up the river, against the
current. Usually the boat end up as lumber in New Orleans, and the trader-pioneer made their long way home on foot. Steamboats
on the Mississippi and Ohio rivers were still only a dream in the minds of so-called "Crack-pot" inventors.

Oliver Evans was the first of America's scientific inventors; that worked out his experiments by means of physics and mathematics,
and designed his machines on the basis of equations. This process, later to be called mechanical engineering, was a departure from the
trial-and-error of the "whittling inventors". Very likely, Evans would not have been at all surprised by any of the inventions of the 19th
or even the 20th century. In fact, he predicted many of these inventions. It was very natural for him to be deeply interested in such a
problems as how to raise wheat in the eastern and western parts of the country, how to make flour from the wheat, and how to move
these products by means of steam transportation.

Born in Delaware in 1755, Oliver Evans took to inventing as the result of an accident to his leg. While away during the time he was
laid up, he worded on a carding machine for wool and cotton. The little cards, which even a child could use, looked like the brushes
used for curryin a horse. The wire teeth combed the wool and cotton preparatory to spinning. In making the cards Evans also
invented a primitive machine for placing the wires, drilling holes in the leather of the card, and performing four operation in one.
Unfortunatly, Evans did not secure patents on either the card or card-maker, and another inventor used the idea. But Evans carried
over his "automation" ideas into his next invention.

In his time, flour milling required strong backs. Bags of grain were carried, step-by-step, to the top of the mill. There the bags were
emptied in a regular flow, first to be cleaned and then crushed by the heavy millstones on the lower floor of the mill. The millstones
were turned by a waterwheel in the river outside the mill. As the meal was ground, it fell into a long narrow through. Then, while still
hot and wet, the meal was again carried to the top of the mill, where it had to be spread out to dry and cool. Men with rakes performed
this process. When the meal was dry, it was dropped through cloth filters to separate the flour from the grain, which is the outer husk
of the wheat. One can imagine that with all this handling, much dust and dirt got mixed with the grain.

It took Evans two years to work out a system for automating this process; that is, for having almost all the work done by machinery.
His plan called for tow sets of conveyors, one horizontal, the other vertical. The vertical conveyor worked on the same principle as the
escalator of today. To his vertical conveyor, which moved over two rollers or pulleys, Evans attached buckets. As the buckets,
loaded with grain, reached the tops of the conveyors, they automatically dumped the grain and moved on down to the lower floor
again. This conveyor distributed the grain by moving it along the curves. The men who had previously raked the grain were replaced
by a hooperboy, to rake, which moved the grain around until it cooled. All of this processes obtained their power from the

With this invention, the milling of flour required only two men, one to pour the grain, the other to nail the tops on the barrels that were
filled with flour. By the time Evans was ready to sell his machinery to the flour millers, he had obtained a monopoly for the states of
Delaware and Pennsylvania. Under this monopoly, only Evans could sell the conveyors. His brother Joseph joined him as a salesman,
but it was not easy to sell an invention that looked as if a blacksmith could make it. There was not law against a man "rigging up"
something to make work easier. At first sales were slow, but bit by bit the millers bought, usually one conveyor at a time. While
Joseph managed the sales, Oliver went on to write his book. "The young Millwright and miller's Guide", which became very popular
was printed in many editions.

In this book, Oliver Evans set forth the transition from the writing, trial-and-error method of invention to the scientific method. The text
contained chapters on mechanical engineering, which was almost unheard at the time, as well as descriptions and drawings of his method
of flour milling by machinery, and his experiments with steam.

Evans devoted the last fifteen years of his life to working with steam. He built a steam carriage, but found it too heavy to run on the poor
roads of the period. Then he pioneered in hight-pressure stationery engines. He built fifty of these engines wich were used mainly for pumping.
One of his most curious inventions was an amphibious steam dredge that could be used on land and on water. In his writings, Evans
prophesied steamboats on the Mississipi, the growth of canals, and the steam railroads that would develop from those that were
horse-drawn. The Erie canal was opened to traffic in 1825 and the Steam railroad came a generation later, just as Evans had predicted.

There is not doubt that this man contribute to the molding of the great North America.

The men who molded North America

Julio Duran

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