MECHANICS AND USEFUL ARTS. 63 



sarily provided with an extra axle (which may be very cheaply fitted, as there 

 is but very little motion), and four extra boxes or bearings. New York 

 Tribune. 



A passenger car, constructed of hoop-iron, has been recently introduced 

 upon the Sixth Avenue (New York City) Rail-road. The car is somewhat in 

 the shape of a coach body, with an entrance for passengers at either end. It 

 is made of hoop-iron, banded together like lattice-work, and weighs about 

 3,500 pounds. It is considerably lighter than the ordinary wooden car, and 

 is easily drawn by t\vo horses. The cost of the car in question was about 

 $1,500. 



APPLICATION OF STEAM FOR AGRICULTURAL PURPOSES. 



At the Annual Exhibition of the Royal Agricultural Society of England for 

 1855. an unusual degree of interest was excited in respect to the exhibition 

 of machines intended to illustrate the application of steam to agricultural pur- 

 poses. For portable steam engines adapted to farm use, eight entries were 

 made, of eight, seven, and six-horse power. The prices ranged from $900 to 

 $1300; the cheapest engine of eight-horse power being entered at a cost of 

 $900. In the trials, the getting up of steam involved a consumption of from 

 18 to 24 pounds of wood, and from 18 to 35 pounds of coal, in spaces vary- 

 ing from 39 to G6 minutes. The quantity of coal consumed (per pound) per 

 horse, per hour, varied from 34- to 10 pounds. The prize was awarded to an 

 eight-horse portable engine, costing $1,250, consuming, in getting up steam, 

 24 pounds of wood, or 28 pounds of coal, in 66 minutes, or 3-^-ths pounds of 

 coal per horse-power, per hour, when in full operation. 



For the prize of 200 offered by the Society for the best steam-plow, tractor, 

 or cultivator, several machines were entered. The most remarkable machine 

 of this kind was a steam "horse" or "tractor," of fourteen-horse power, ex- 

 hibited by Mr. Boydell. This is a carriage that takes its own railway along 

 with it rails, plank-bearings, and all and keeps putting down and taking 

 up its track as it proceeds. This strikes one at first like the idea of getting 

 into a basket and lifting yourself by the handles, but the editor of Chambers 's 

 Journal has seen the machine operate, and thus describes it: 



" It is evident that a flat deal-board will not, weight for weight, sink so far 

 down into a bed of mud as will the narrow tire of a cart-wheel. It is evident, 

 too, that cart-wheels may have a railway tire or edge, instead of an ordinary 

 tire or edge : and that a line of rails admits of being laid down upon a wooden 

 plank. A person, likewise, may readily conceive the idea of laying down one 

 of these rail-planks under each wheel ; and this, indeed, is very much like 

 what is ordinarily done in the construction of a common railway. The prob- 

 lem, therefore, was this : to construct the wheels in such a manner, that by 

 means of certain mysterious-looking levers, pins, screws, and iron arms, these 

 railway -planks, when passed over by the wheels, should be taken up by the 

 machinery, and laid down in a new spot ; and this problem has actually been 

 solved. Each wheel admits of being represented as consisting of a circle in- 

 scribed within a hexagonal frame of flat boards, each furnished with railway 



