27 



Ur. George Mathews, engraver of this city, called the 

 Canada Banknote Printing Tint. The green pigment which 

 forms the basis of this ink resists all acids, alkalies and 

 other agents, which can be applied to the paper. It is the 

 permanent of colors, and as indestructible as the carbon 

 of the ordinary black printing ink. I have the honor to 

 be, sir, Your most obedient servant, 



''THOMAS STERRY HUNT." 



Subsequently Hunt took out a patent for an ink made from 



stannic acid with small proportions of oxide of chromium, 



forming what lie called Mineral Lake, but neither this nor 



any of his patents yielded him much revenue. While 



scrupulously honest in all pecuniary transactions, he did not 



-ess the money-making instinct. 



To the metallurgy of copper he was introduced by his 



'1, J. D. Whelpley, well known as one of the brilliant 

 men on the staff of the first Pennsylvania Survey. Mr. 

 Whelplev, in company with Col. Storer, had devised a wet 

 method for treating copper ores, which was to be carried out 

 by the employment of a number of novel mechanical 

 devices. Hunt worked out the chemical reactions, and 

 reduced them to formula-. The method never came into 



ical use. It was while endeavoring to apply it that 

 Hunt and 1 patented in ISM) the use of chloride of iron in 



ction with common salt as a solvent of cupric and 

 cuprous oxide, and subsei|uently in 1871 our investigations 

 and tin- inadequacy of our previous jm-th.nl to the treatment 

 of sil ;ing ores, led us to patent a method in which the 



er is separated from its chloridized solution as insoluble 



'iloride. through the action f sulphurous acid. On the 



lation of su< i.-al subjects, he brought to bear hi> 



intimate knowledge of clx-mical reactions and his habits.of 



rob, and therefore his papers on such suhj. 

 have .niral bearings. 



rulrs of the Geological Snrvev laid down by Sir 

 Logan 



i.-ida or to report ,,n mining pn- 



