194 [Assembly 



1 have been engaged over forty years in hemlock tanning; and 

 of the many books which treat of the process of tanning, none 

 have been found which give any information of the mode of hem- 

 lock tanning. The bark has scarcely ever been analyzed for the use 

 of the tanner; and the knowledge which I have acquired, has been 

 the result of long continued practice and experience. This teaches 

 one that the hemlock is much stronger than the oak. 



The tanning of leather, more than almost any other manufacture, 

 is a chemical process, the success of which depends almost wholly 

 upon the skill and judgment with which its complicated manipula- 

 tions are conducted. To attaiij the requisite skill in the laboratory 

 of the chemist, is evidently impossible; it can only be acquired in 

 the tannery itself, by long and careful attention and observation; 

 and, perhaps, there is no description of manufacture, where more 

 depends upon practical knowledge, and so little upon mere theory, 

 as in the tanning of leather. The tanning of leather consists in 

 effecting a combination between the gelatine, which is the main 

 constituent of raw hides, and tanning a peculiar substance found in 

 the bark of several species of trees — the oak and hemlock, chiefly. 

 The processes employed are so various, and quality antl condition of 

 the hides are so numerous and so different, that hardly any branch 

 of business requires for its successful conduct a greater degree of 

 judgment and experience; and in few arts have there been greater 

 improvements. 



