A reprinted report from the U.S. Commissioner of Agriculture for 1871 about steam power and steam plows
Parvin's Traction Engine. (Patented October 10, 1871)
Before leaving the department of plows, a word must be said in reference to those which are impelled by steam power and steam plows. A brief mention will suffice, for though we find no less than thirteen patents in this class for the year, but few of them are deemed worthy of special notice.
Of these thirteen, one is intended to be dragged across the field by means of a chain or cable and stationary engine, according to the well-known plan. The improvements claimed are of minor importance, and are merely intended to increase the efficiency of the machine. The other twelve carry their own power. Of these, two belong to the class known as rotary spaders. Among the ten may be found two provided with propelling legs, designed to push the engine and plow along; another claims as an improvement the provision of blocks shaped like a horse's hoof, and placed upon the periphery of the traction wheels. In another, the machine carries and lays its own track in the manner of some road engines, causing a rotary motion in a horizontal shaft located at or near the hind part of the bed. This shaft is connected by suitable gearing to a driving wheel suspended beneath the bed of the engine. This driving wheel, it is understood, does not touch the ground, but is provided with an endless chain, the alternate links of which are made with ridges that mesh into suitable recesses on the periphery of the wheel. At some distance in front of this driving wheel is located another wheel of like dimensions and construction, hung in a similar manner. The endless chain referred to also engages with this wheel, so that when steam is applied, the wheels are revolved and the chain travels over them. At regular distances along this chain is placed a series of metal plates, constituting the feet of the machine, and shod with wooden shoes about two inches thick. At each end of the feet is placed a roller of some ten inches diameter, and upon these rollers rest the tracks or ways attached to the underside of the bed of the engine. Thus it will be seen that the body of the engine rests and moves upon a series of rollers attached to feet, which are automatically raised from the ground, carried forward, and deposited again in front, to be passed over regularly. In other words, the machine carries and lays its own track. Its operation is precisely as if a series of rollers were attached to ties laid in a straight line across the field and the engine dragged over them. The only difference is, that in this case the ties are chained together and are picked up, carried along, and used continually. The construction will easily be understood by reference to the well-known endless-chain horse-power. The means used in the case under consideration to propel the carriage consist of just such an endless carrier, arranged to come in contact with the ground two feet being always on the ground and three off. It ought to be remarked that this principle of propulsion for steam-plows is not for the first time applied. In this case the real novelty, aside from the detail, consists in combining the traveling feet with suitable guiding mechanism. The engine is guided by means of two forward wheels mounted on pivoted axles, and so arranged as to be turned right or left at will. The plows, which are of ordinary construction, are connected to the rear part of the machine, and are arranged for the necessary vertical adjustment.
We are informed by a correspondent who witnessed the operation of this steam plow last fall in a field near Philadelphia, that it did some remarkable work. The engine itself appeared to be defective mechanically, and open to improvement, but the method of traction and guidance seemed to work well. On the occasion referred to, a gang of six plows was attached to the machine, steam was got up, and the engine started. The field was traversed for about a quarter of a mile, the plows being pushed in almost to the beam, and the engines moving at a rate that required pretty rapid walking to keep up with it. On reaching the end of the field the plows were unyoked and the engine turned around. The plows were then again connected with the engine and a return to the starting-point made. There were the hitches and balks incident to a first trial, but the experiment was measurably a success.
To afford an opportunity to those interested in steam-culture to study the inventions thus briefly mentioned, we append a list of the patents granted during 1871 for steam-plows and land-carriages, or traction engines designed for drawing plows. The specifications may be had on application to the Commissioner of Patents; the cost of the specification and drawing in each case being but 25 cents, or 10 cents each when twenty or more are taken.
I. P. Tice, Steam Plow, patent 111,404 granted January 31, 1871.
O. Hyde, Elastic Tire for Traction Engines, patent 111,213 granted January 24, 1871; Improvement in Steam Plows, patent 120,071 granted October 17, 1871.
S. H. Gibbs, Improvement in Rotary Spading Machines, patent 116,297 granted June 27, 1871.
M. M. Lynn, Motion for the Pushing of Legs of Steam Plows, patent 116,610 granted July 4, 1871. Steam Carriage, patent 117,307 granted July 25, 1871.
H. Miller, Steamplow, patent 118,143 granted August 15, 1871.
W. C. Bibb, Steam Wagon and Plows, patent 119,216 granted September 26, 1871.
Robert C. Parvin, Improvement in Traction Engines, patent 119,878 granted October 10, 1871.