ELISHA MITCHELL SCIENTIFIC SOCIETY. 



31 



weighings were made from each bottle which was unavoidably kept 

 open during the process of each weighing — the bottle in the mean- 

 time subjected to the ordinary heat of the laboratory. 



To test this theory of loss in moisture I selected six samples of 

 ammoniated fertilizers entirely at random from a lot of thirty or 

 forty. The first determination of moisture was made one hour after 

 sampling, and the second after the lapse of one month — with the 

 results given below : 



TABLE I. — Moisture at 100 C. 



TABLE II. — Decrease of Moisture. 



No. I has decreased in moisture in 30 days, 0.81 per cent. 



-1.79 



- -72 



- .21 



-1-33 

 .1.02 



Table II shows an invariable decrease in moisture, which has the 

 effect of elevating the per cents, of the other constituents to a 

 marked degree. For example, in No. 2 where the decrease is great- 

 est, the sample contained at the time of the first weighing 9.77 per 

 cent, total phosphoric acid. Theoretically this would be raised at 

 the second weighing, on account of the loss of 1.79 per cent, mois- 

 ture, to 9.98 per cent., an increase of 0.21 of total P0O5. Practi- 

 cally this increase was found to exist, by actual analysis, 30 days 

 after the first determination. 



