EFFECTS OF PRESSURE ON NITRATES. 625 



grams of all five nitrates tend to the same simple type; the disturbing 

 complications are found only at low pressures. 



Acknotoledgment. I take this occasion to make grateful acknowl- 

 edgment of liberal grants from the Bache Fund of The National 

 Academy of Sciences and from the Rumford Fund of The American 

 Academy of Arts and Sciences, with which the expense of mechanical 

 assistance and materials has been met. 



The Jefferson Physical Laboratory, 

 Harvard University, Cambridge, Mass. 



