6o JOURNAL OF THE 



becomes insoluble in citrate even at 90°. In other words, the per 

 cent, of Insol. Phos. acid varies from time to time. In reflecting 

 upon this subject, there was reason to suspect that this variation 

 was largely controlled by the mechanical condition of the analytical 

 sample. Some experiments w^ere begun on this point, but could not 

 be carried through, owing to the pressure of routine work. In pass- 

 ing an article of 6 per cent, or 8 per cent, moisture through a 40 

 mesh seive, a good deal of it must necessarily be pulverized finer 

 than the seive. The less moisture the article holds, other things 

 being equal, the more will tlipre be of it much finer than the seive. 

 The citrate acts upon this fine stuff more effectually than upon the 

 coarser, and in this way the variation of the Insol. Phos. acid may 

 be partially explained. Doubtless this has some eifect, for from the 

 7th through the 14th week, Tables II and Y, when the moisture 

 varied from 8.22 per cent, to 5.17 per cent., there was a loss of insol. 

 phos. acid all the time. 



Other interesting points might well be considered did this space 

 allow. Such as they are the careful reader will recognize. It is 

 hoped to follow up this discussion with some parallel observations 

 as soon as possible. 



Laboratory of the Navassa Guano Company, ) 



Wilmington,, N. C. ^ 



NORTH CAROLINA PHOSPHATES. 



W. B. PHILLIPS. 



{Abstract from Thesis for Ph. D.) 



So much has been said and written about North Carolina Phos- 

 phates during the last six months, that it appears necessary now only 

 to give an abstract of the first detailed investigation of the subject, 

 together with such additional infonnation as has been acquired by 

 t'ie writer up to this time. 



It can hardly be said that the true Phosphate Rock (of value to 

 be worked without concentration) had been noticed in North Caro- 



