G. H. Williams — Rook-cutting Machine. 



103 



The accompanying cut of the machine (fig. 1) hardly needs 

 any explanation. It is seen to consist of a substantial table, 

 carrying in its lower part the electric batteries and motor 



Fig-, l. 



while upon its upper surface is placed the apparatus for 

 grinding and sawing. 



The table is approximately three and one-half feet square 

 and two feet nine inches high. It is constructed with all of 

 its appurtenances by the Donaldson- Macrae Electric Com- 

 pany of 215 N. Calvert St., Baltimore, whose storage batteries 

 and electric motors are well known. The price of the ma- 

 chine complete is $130.00, consisting of the following parts : 



1. Three two hundred ampere-hour storage batteries, 13 

 inches high, in portable rubber cases. These batteries stand 



Am. Jour. Sci.— Third Series, Vol. XLV, No. 266. — February, 1893. 



8 



