LEA THER-MAKING. 



357 



the desired thickness by hand, entailing obviously a great waste 

 not only in time but in the large portions of the hide which it was 

 necessary to throw away. By the use of these machines, however, 

 these same hides may be split into two, three, or even five parts, 

 of such thickness as is desired, and each part rendered available. 

 This machine was not really perfected until about 18G0. As early 

 as 1800 rough attempts had been made to split leather by ma- 

 chinery, and in 1809 Seth Boyden, of Newark, N. J., secured a pat- 

 ent for such an invention. But there were serious obstacles which 



Fig. 17. Bakk Mill. 



rendered it impracticable, and it was left to the ingenious mind 

 and skilled hand of Alpha Richardson, of Boston, to overcome 

 them. He secured his first patent in 1831, but he continued to 

 make improvements upon this device until 1856. Then all were 

 grouped, and what is known as the Union splitting machine was 

 the result. This machine is the one which is now in common use 

 among American tanners. Its machinery is somewhat complex. 

 It consists of a small cylinder upon which is placed the hide or 

 leather to be split. As this cylinder turns, the leather is drawn 

 against a sharp knife firmly bolted to the bed of the machine. 

 Above the knife is a stiff spring which holds the leather closely 

 to the edge of the blade, and a gauge-roller, which by means of 



