F. W. Clarke on Atomic volumes of Liquids. 185 
In the case of silicon, thanks to the labors of Friedel, Crafts, 
and Ladenburg, materials were more abundant. Apart from 
the chlorid and bromid, whose atomic volumes were determined 
y Kopp, I have calculated the vapor volumes of sixteen liquid 
compounds of silicon, and thence the atomic volume of silicon 
itself. These compounds are tetramethyl, tetrethyl, and tetra- 
pounds. The atomic volume of titanium, as deduced from 
that of the chlorid, as determined by Kopp, is 34:8. Further 
This gave for tin the number 402. The vapor volume of 
the same compound gave as the atomic volume of tin, the 
40- 
Owing nine compounds containing this metal. Stanntetre- 
thy), stanndimethyl diethyl, stanndiethyl, stannethyl trimethyl, 
the chlorid, bromid, and iodid of stanntriethyl, and the iodids 
of stanntrimethy] and stanndimethyl. From the vapor volumes 
of these liquids I have obtained respectively as the atomic vol- 
ume of tin the numbers 46°5, 42°0, 39°3, 44:0, 57:7, 42°1, 41-0, 
418, and 44-0, Including the number deduced from the chlo- 
ud of tin, we get as the average 41:8, the atomic volume of tin 
in its liquid compounds. 
‘n the case of zinc there were but three liquid compounds for 
Which I was able to calculate the vapor volumes. _ These were 
“inc ethyl, zinc methyl, and zine amyl. The atomic volume of 
| “uc, deduced from their vapor volumes, I obtained respectively 
88 23:2, 242, and 23-2. The average is 23°6. 
| , Of liquids containing selenium I have the vapor volumes of 
} but two,—the oxychlorid, SeOCI,, and monohydrated_selenic 
_ The latter of these, however, has never been k 
Jour. Sct.- -Seconp Serres, Vow. XLVI, No. 140.—Mancu, 1869. — 
13 os 
