198 FE. & Dana—Crystalline form of 
100° after some time. The triclinic crystals seh ges rapidly 
a few degrees lower than the monoclinic. Bot S appear 
yields on recrystallization some monoclinic crystals. 
s to the constitution of the bodies their reactions make evi- 
dant: that they contain the ethylidene and nitro groups. ie 
gous to the ammonio-silver nitrate, whic 
may een “regard them as amines, a may show their rela- 
tion to ammonia-silver nitrate as follow 
HN CH ae 
HN { AgNO; CH? —CH=NH f AENOs 
In accordance with the requirements of the now received 
theories, these bodies may be formulated as substituted ammo- 
nium nitrates, viz : 
H,=N—O-NO,, ammonium nitrate. 
H N= =—N—O-NO, argentamine-ammonium nitrate. 
Ag 
Hy 
CH ,CHN—O—NO, neers eer mg 
WT ethylidenammonium nitrate. 
CH, Essen 
Ag 
Art. XX VIT.—On the e crystalline jorm of the ei and anhy- 
drous varieties of Ei 
Nitrate; by Epwarp S. Dana. 
A: Hydrous y 19 Pe Be 4 * ae Ue) os Nitrate. 
ve 
7 am 
THE nyliigad variety of etl 
monium nitrate, described by Bratece! Mixter i in te preceing 
article, crystallizes in the monoclinic system. The observ 
planes (see figs. 1, 2) are as follows: 
e (001), d oe g (111), ¢ (011), and rarely 5 (010). 
ement of a considerable number of stent 
the following were 2 vbicead as the fundamental angles 
