28 PROCEEDINGS OF THE AMERICAN ACADEMY 



length of 2-3 mm., but they are usually much smaller. The substance 

 undergoes no visible change when heated to about 300° ; at a higher 

 temperature, it melts with complete decomposition, and without per- 

 ceptible sublimation. It is soluble in boiling water, almost insoluble 

 in cold water or in boiling alcohol ; insoluble in ether. Cold concen- 

 trated sulphuric acid dissolves it abundantly ; upon dilution it crystal- 

 lizes out, apparently unchanged. Air-dried it contains water, a portion 

 of which it loses at 100° ; the rest slowly, but completely, at 160°. 



1.3887 grm. substance air-dried lost at 165° 0.1124 grm. = 

 8.09%. 



The formula C5H3(CH3)N^03 . Hp requires 9.00%. Of substance 

 dried at 100°: — 



1. 0.7772 grm. lost at 165° 0.0399 grm. = 5.13 %. 



2. 0.4953 „ „ 0.0289 „ = 5.83 %. 



3. 0.4670 „ „ 0.0238 „ = 5.10 %. 



4. 0.8106 „ „ 0.0451 „ = 5.57 %. 



The formula C5H3(Cri3)N,03 . iHp requires 4.77 %. 



from these determinations, it would appear that water is not a 

 definite constituent of the compound. The microscopic appearance of 

 the substance remains unchanged. 



The substance dried at 165° has the formula 05113(0 H3)N^03, as 

 the following analyses show: — 



1. 0.4284 grm. gave 0.1310 grm. 11,0, and 0.6210 grm. OO2. 



2. 0.2748 grm. gave 0.0985 grm. II.p, and 0.3972 grm. OO2. 



3. 0.1822 grm. gave 50.0 cc. nitrogen, at 20°.o, and 754.3 mm. pressure. 



Calculated for Found. 



0,H,N,03. 1 2 3 



39.56 39.53 39.43 



H 3.30 3.39 3.98 



N 30.77 30.98 



To determine the solubility in boiling water, a boiling saturated 

 solution was filtered through a hot, water filter into tared fiasks. After 

 cooling, the flasks were weighed, the contents washed out, evaporated 

 in platinum, and the residue dried at 165°. 



1. 52.290 grm. solution left 0.2043 grm. residue. 



2. 55.379 grm. solution left 0.2187 grm. residue. 



The boiling saturated solution contains, therefore, the percentages, — 

 1 2 



0.3906 0.3950 



