Figure 46. — Pagl from pattern book by James H. ChappcU dealing witli liis splierical s\sicin uJ lailuiing. 

 Patent issued January 18, 1834 (restored patent 7962X). 



The historian engaged in restoration and preserva- 

 tion is ill advised to bypass the Patent Office. Early 

 industrial techniques such as charcoal burning (fig. 

 51) and bark grinding (fig. 52), vehicles of all types 

 from fire engines (fig. 53) to gigs (fig. 54), agricul- 

 tural implements by the score (fig. 55), and a variety 

 of other tools are represented by watercolor drawings 

 or specifications or both. Thomas W. Pryor's im- 

 proved bark mill of 1805 is an excellent example of 

 the patent record as an illustrative and descriptive 

 document. The drawing (fig. 52) shows a typical, 

 horse-powered, bark mill complete with the miller 



and his horse, while the specification outlines the 

 process. 



Bark, after being prepared in the usual manner is thrown 

 into a Horizontal Separating Machine, which is a CN'lindrical 

 Revolutionary Wire finer or coarser as may be foimd most 

 advantageous with Interstices to produce long or short 

 filaments of Bark . . . ; the separated Bark falls into a 

 Chest below the Separating machine, throwing out at the 

 end. The unsmashed lumps or pieces of Bark which may 

 not be sufficiently ground . . . are placed in a Common 

 Bark mill and after being reground is thrown into the 

 Separating machine and goes through the foregoing process. 



144 



BULLETIN 24 1 : CONTRIBUTIONS FROM THE MUSEUM OF HISTORY .■XND TECHNOLOGY 



