416 



TABLES. 



little vinegar or tartaric acid, or cream of tartar ; remedies 

 always at hand. 



**To insure perfect freedom from protoxide of iron, 

 I would always pass a current of chlorine, through the 

 solution of prepared nitrate of iron, before that is con- 

 sidered as fit, to be kept on hand, for the ready formation 

 of hydrated peroxide of iron. 



TABLES: 



SHOWING THE PROPORTION BETWEEN THE HESSIAN AND 

 ENGLISH STANDARD OF WEIGHTS AND MEASURES. 



In general all the weights and measures employed in this 

 edition are those of the English standard. In a few cases 

 only, the Hessian weights and measures have been re- 

 tained. In these the numbers do not represent absolute 

 quantites, but are merely intended to denote a proportion 

 to other numbers. This has been done to avoid any un- 

 necessary intricacy in the calculations, and to present 

 whole numbers to the reader, without distracting his at- 

 tention by decimal parts. For those, however, who wish 

 to be acquainted with the exact English quantities, a table 

 is here given below. 



1 lb. English is equal to 0-90719 lb. Hessian; hence, 

 about one-tenth less than the latter. 



1 



2 



3 



4 



5 



6 



7 



8 



9 



10 



20 



30 



40 



50 



60 



70 



80 



90 



100 



200 



lb. Hessan is equal to 

 lbs. Hessian are equal to 



m 



