S. P. Sadtler on Iridium Compounds. 343 
In ‘another preparation, also indistinctly crystallized, 3207 
grms. dried at 100°: 
gave ‘2125 grms. AgCl = 1268 grms. Cl = 39°53 pr. ct. 
It will thus be seen the determinations, all things considered, 
agree close enough with the theoretical pr. cts. of the formula 
to make it very probable. The want of enough sufficiently- 
well crystallized material prevented me from making an organic 
combustion which might settle it definitely. 
Several individual crystals of the first crystallization were 
very sharply and clearly formed, and I subjected them to 
examination under the microscope with a power of about 50 
diameters. The faces were clearly to be made out. ey be- 
long to the monoclinic system, and their prevailing habitus in 
crystallization is a combination of the two lateral pinacoids 
with positive and negative pyramids accompanied by one mac- 
todome on the ends. The faces observed in an examination of 
five distinct crystals were (according to Naumann) «Po. 
ePo +P.—P.4¢P.-¢P.4+Pa.-Po 
In considering the compounds of the iridium-base with 
NH,Cl, we find again a mixture of crystallized salt: 
Preparation No. 1 consisted of sharply crystallized needles 
that looked almost black, and only by transmitted light showed 
a brownish-green color. ey were also monoclinic. 
_ On analysis they prove, I think, to be the sought-for ethylen- 
indium compound. i 
‘0713 grms. dried over H,SO, lost on heating to 100° 0029 
r. ct: 
gave “0850 grms. AgCl = 0210 grms. Cl = 29-49 pr. ct. or 
= 28°98 pr. ct., H,O —'4-89, or anhydrous 30°47 pr. ct. Cl. 
Parton ‘No 2 was of much smaller needles and of lighter 
color. c 
Analyses show it to be of very similar composition to the 
potassium salt described above. 
‘1207 grms. dried at 100° C. : 
gave 0495 grms. ie Age i. = Fe = pr. ct. = 
ve also -2068 germs. AgCl = ‘0512 grms. Ul — 
il, (C my, (NHL.Cl), = 502 gives Ir. = 39°20 pr. ct. and 
Cl = 49-43 pr. ct., and supposing it to lose s thi aoe hos 
100°, as stated above, Tel (C.H .) (NH, Cl), would give Ir. = 
e other two preparations of the ammonium salt — 
appeared under the lens to be mixtures of the iridium proto- 
