23 



[No. 1 is a specimen obtained from the factory. No. 2 is a 

 specimen obtained from the agent in Albany.] 



ANALYSIS OP ASHTON SALT. 



A. B. 



Chloride of Sodium 97.59 p. c. 97.660 p. c. 



Sulphate of Lime 1.67 p. c. 1.381 p. c. 



Chloride of Calcium 0.01 p. c. 



Chloride of Magnesia 0.03 p. c. 0.059 p. c. 



Water .- 0.70 p. c. 0.900 p. c. 



100.00 100.00 



[The analyses of the Ashton salt were made by Prof. Cook ; 

 that of A. is given in the Report of the Superintendent of the Onon- 

 daga Salt Springs, 1854, p. 10. The second, B., was made later, 

 and was regarded as " a good specimen."] 



The Ashton salt was selected for comparison because of its 

 high reputation among dairymen. From the analyses just given, the 

 comparative purity of the two varieties of salt may be judged. 



6th. As regards the absorption of water, by salt, an erroneous im- 

 pression is prevalent. Pure salt, it is generally believed, will not 

 absorb moisture, even in a damp atmosphere. Such is not the fact. 

 When the atmosphere is moderately dry, pure salt will remain 

 unaffected, but when the air contains much moisture it will deli- 

 quesce, becoming damp in proportion to the moisture in the air. 

 The water in the specimen of Onondaga Factory-filled Dairy Salt, 

 taken in Albany, (No. 2,) probably does not fairly represent, but 

 is greater, than the amount of water ordinarily contained in it. 

 The specimen was taken from the storehouse on a damp day, and 

 was conveyed to my laboratory in a bag. My limited time did 

 not allow rne to make other experiments upon this subject. It may 

 be mentioned here, as illustrating the point under consideration, 

 that the Ashton salt varies considerably as regards the moisture it 

 contains, (as indeed must every salt,) thus the same specimen was 

 found to contain in different states of the atmosphere, as regards 

 dry ness, from 0.71 to 0.06 p. c. of water. To obtain a just estimate 

 of the character of different salts in this respect, so that correct 

 comparison may be made, the examination ought to be conducted 

 at the same time, upon specimens subject to the same conditions. 



7th. Hardly less important than the manufacture is the man- 

 ner of storing and shipping salt; great care exercised in the first, 

 may be to a great extent neutralized by carelessness in the second. 

 The manner of conducting the manufacture and treating of the salt 

 at the Onondaga works, was apparently that best fitted to remove 

 impurities and to prevent the introduction of foreign matters. The 

 salt seemed to be carefully stored and protected from dust and 

 dirt. The barrels in which the salt was packed, at the time of my 



