VI] LEATHERS 61 



9 DETEKMINATION. 



Determine dextrose in 50 cc. of the solution, as prepared under 8, equivalent to 

 0.5 gram of leather, according to VIII, 25 and express the result as glucose. 



I TOTAL SOLIDS. 



Determine as directed under V, 2. 



I I SOLUBLE SOLIDS. 



Determine as directed under V, 4. 

 1 2 NONTANNINS. 



Determine as directed under V, 7. 



1 3 SOLUBLE TANNIN. 



The difference between the percentage of the soluble solids and the corrected 

 nontannins is the percentage of tannin. 



1 4 NITROGEN. 



Determine as directed under I, 21 . 

 1 5 HIDE SUBSTANCE. 



Multiply the percentage of nitrogen by 5.62. The result will be the percentage 

 of hide substance present. 



16 COMBINED TANNIN. 



Deduct the sum of the percentages of moisture, under 2, insoluble ash, under 4, 

 soluble solids, under 1 1 , and hide substance, under 1 5, from 100. The result will 

 be the percentage of combined tannin. 



BIBLIOGRAPHY. 

 » J. Am. Leather Chem. Assn., 1915, 10: 122. 



