AGRICULTURAL MECHANICS AND RURAL ECONOMY. 89 



industry, we notice the very general introduction of the rotary cultivator. This improve- 

 ment seems to present some advantages -which are -worthy of attention ; and to render it 

 more clear to the general reader, we will describe its construction : — 



The frame A B supports three sets of coulter or toothed wheels ; the first set, a a, are 

 merely circular rotary coulters, and are made of the usual plow steel, or, for general pur- 

 poses, of cast iron, as thin as is consistent with due strength ; they are bevelled to an edge, 

 and at the height of the bevel are slightly thicker than in the interior part, to lessen friction. 

 Their distance apart may vary to suit the soil intended to be cut through. 



The second and third sets, b b and c c, are so placed as to come alternately in the centre 

 of the sections made by the first set, and consist of a coulter precisely like those of the first 

 set a a; their edges are set with wings or knives w w, projecting laterally at such an angle, 

 that, as the wheel revolves and advances, they descend edgewise with the least practical re- 

 sistance, and come up flatwise, bringing up the earth from the bottom of the cut. 



The inclination of these knives, and the effect of their position, is shown in fig. 2, in which 

 the lines op show the direction of the plane of the knives, and their length is equal to the 

 space between the coulter a a, so as to cut up all the earth as the machine passes over it. 



The advantage of the circular form of knife is, that all hard substances, such as loose 

 stones, are pressed one side, and they are made adjustable, so that if one breaks, it may be 

 conveniently replaced. The patent provides for an increase of the coulters or wheels, and 

 also for the attachment of the cultivator to a carriage, whereby it may be raised and lowered 

 at pleasure when formidable obstacles are presented ; and each coulter or wheel may have a 

 separate axle, and play up and down under the pressure of a weight or spring, thus readily 

 adjusting itself to uneven surfaces. 



Trial of Plows at the Paris Exhibition. 



During the progress of the National Exhibition at Paris, during the past summer, a trial 

 of the various plows exhibited was made. The one found most effective was an English 

 plow, contributed by Messrs. Howard, of Bedford, England. This plow, as carefully tested 

 by the dynamometer, on clover sod, being drawn by two smartly-walking horses, turned a 

 furrow ten inches wide and six and a half deep with a medium draught of only one hundred 

 and eighty-two pounds, or a little more than half its own weight, (over three hundred 

 pounds.) There are a good many men who could draw this plow at that gait, and almost 

 any two men could easily do it. There were no plows entered from the United States, there 

 being none on exhibition ; but one from Canada was tried, and did good work. Most of the 

 plows entered from the continent proved beneath contempt, as was to be expected. Some 

 of them required over quadruple the power to propel them that was exacted by the winner ; and 

 one from Austria, that was confidently bragged on before the trial, actually twisted around, 

 broke off, and gave up the ghost, in light clover soil, free from root or stone, and with but a 

 single span of horses before it. — New York Tribune. 



Knox's Horse-Hoe. 



The construction of this hoe may be understood by conceiving of the handles and beam of 

 an ordinary plow, having two pieces of wood running backward from its sides, letter A-fashion, 

 at a point near the place where the horse is to be attached to the beam. At the point of the 

 main beam in which these two sides meet is a cimetar-cutter or coulter, the office of which 

 is merely to enter the ground and steady the machine during its action. At each of the 

 other extremities of the two arms formed by the letter A is a miniature plow. In the rear 

 of the main beam, and directly under the handles, is placed a V-shaped share, point for- 

 ward. Upon the rear of the wings of this share are teeth, each tooth being about three 

 inches long, and projecting backward. A wheel and regulating clevis are placed upon the 

 front of the beam, to which the horse or mule may be attached. 



The action of this hoe is as follows : — The cimetar-cutter, as already stated, steadies it ; 

 the miniature plows throw the soil to the centre, and the comb again distributes it. Let it 



