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XVL Description of a new Thrashing Machine. By 

 Richard Tawney, Esq. 



To Mr. Tilloch. 



Sir, It having been long thought in this part of the 

 kingdom a desideratum to uiiite in a thrashing machine with 

 a small power the qualities of clean and good work ; the 

 following description, accompanied by a drawing of one 

 which a short time since I had made for my own use, and 

 which most effectually answers the purpose, will, perhaps, 

 be not unworthy a place in the Philosophical Magazine. 



I was induced to the attempt by observing that in every 

 machine in this neighbourhood, both fixed and portable, 

 a very large portion of the power was lost by friction, 

 seldom less than half, and wished to try what could be ef- 

 fected by a machine constructed with a view to reduce the 

 friction as much as possible. 



The drawing presents an elevation and section of a ma- 

 chine to be worked by two men, with each a winch upon 

 the axis of a wheel (which, as they could not be well shown 

 in a geometrical view, are purposely omitted) turning by 

 a small rope a pulley fixed upon the axis of the drum. 



It will be seen that the wheel is hung upon friction rollers, 

 and it was my intention to have put rollers to ihe drum axis 

 as well ; but as these were found to enhance the price, and 

 thereby defeat the general utility of the plan, the latter 

 were omitted, and the friction kept down by making the 

 brasses and axis as perfect and as small as they well could 

 be with safety. 



It should be mentioned that the drum, rollers, and plates, 

 are upon the principle of the machines made by a Mr. 

 Wilson, of Leicester, which for quantity and goodness of 

 work are the best of a great number that I have seen. In 

 these macliines, as will be observed in the section, the 

 feed rollers are placed horizontally, and they are fed by 

 laying the corn upon a board inclining to them from tho 

 top. One roller is turned by a small strap from the drum 

 axis ; and as the two are made to touch by a thin well 

 turned iron wheel or flanch at each end, the other roller is 

 moved by friction. — Lest this should be thought strange 

 in a machine purposely made to avoid friction, it must be 

 remembered that, as the wheels are small, the points of con- 

 tact are trifling, and that there are no other means of ob- 

 taining an equable motion so good. 



Voi.AQ.UQ.il^. AugyLst \^\'2. F The 



