SEVERAL MECHANICAL INVENTIONS. 149 



prove of greater value, when applied to shear the fibres off 

 from surfaces without injuring them. 



About six months after my specification of the patent 

 appeared in the 'Repository of Arts/ I found that a 

 patent had been taken out for chopping straw, roots, &c., 

 by employing the same action of revolving spiral cutters 

 against a fixed straight cutter; and this patent had a 

 great run as a useful agricultural implement, which, as I 

 was informed at the time, yielded a large profit to the 

 inventor ; and, in the ordinary acceptation of the term, it 

 was an invention. But the principle of it was evidently 

 derived from the fur-cutting machine ; and doubtless, if I 

 had then possessed the art and mystery of claiming under 

 patents for one purpose their application to many others, 

 I might have then forestalled all of the subsequent uses 

 of the revolving spiral cutters which were successively 

 patented, besides that .for straw-cutting — namely two or 

 three patents for shearing the naps from cloths : some of 

 these were very ingenious and valuable machines, but 

 they are direct copies from the fur-cutting patent. This 

 same principle has been applied in various ways since in 

 preparing dye-stuff, paper-making, and others j but without 

 stopping to notice them separately, it will suffice to men- 

 tion the lawn-mowing machines, now much in vogue, which 

 are from the original fur-cutter. 



