BULfeS TOR INVENTION. J QQ 



II. Much force is lost, being unnecessarily expended in well as the 

 beating the straw, yet many heads escape undone, because fj* ce ; i 08 ' t# an 

 the force is so irregularly applied. 



III. In treading by horses the grain as well as the straw m. Cattle 

 gets dirty make grain 



IV. Thrashing by men is both expensive and tedious. ' 



Now cannot improvements be made to overcome all these Thrashing is 



disadvantages ? Such speculations have produced several. expensive and 



First, a machine on the principles of a coffee mill, which __ ' . 



r r Machines al- 



requires very Jittle force to rub the grain out of the beads, ready made. 



which are separated from the straw, by means of a machine on va) A mill to 



, .... . rr- ~~, . ri,h tIie g rai & 



the principle ot a comb, cutting them oft. A machine to reap f rom the 

 the heads without the straw is wanted to complete this theory, heads, 

 (in countries where the straw itself is not an article of demand). 



Secondly, a machine invented and put in practice by Colonel (b) Revolving 



Cylinder with 



Alexander Anderson, of Philadelphia j the principles of which beaters on its 

 are to apply the strength of horses to strike the straw regularly circumference, 

 with a uniform force* which finishes as it goes and clears the use< j ; n £^. 

 grain at the same time. ■ gland. 



A Cylinder, 4 feet long, and 3 feet 6 inches diameter, with 

 eight bats fastened to .its circumference parallel to it axis, and 

 of its whole length, is made to revolve with rapidity j the bats 

 strike the straw at every fourth of an inch, it being drawn into 

 the machine by and between two collars that move slowly. 

 This machine makes great dispatch, but is expensive, (and 

 destroys the straw.) 



Others, attending to the principles of treading, have made a (c) a rolling 

 thing in the form of the frustrum of a cane or sugar loaf, set cone with cpgi 

 full of cogs to act like the horses' feet. This is drawn by 

 horses round a circular floor, adapted to it, on which the grain is 

 laid, the centre of the circle being the vertex of the cone. 

 This having considerable weight and many cogs, a horse will 

 beat out much more with it than with his feet, because it will 

 strike a great many more strokes with equal force : it has these 

 advantages; it can be made by an ordinary carpenter — is cheap-— 

 and the dirt is not mixed with the grain, straw, &c. 



Example II. The art of cleaning grain by wind. Example n 



By the rule. Art of winner 



Step 1. what are the principles on which the art is founded jt s principle. 

 Bodies failing through resisting mediums, their velocities are as i:i S hi bodie* 



