Under the title of "Figures Worth Studying," Mr. William Farmer, of New
York, read a paper before a recent meeting of the Society of Gas Lighting,
from which the _American Gas Light Journal_ gives the following:

I have prepared the following table, which contains some of the elements
and compounds, with their combining weights, volumes, and specific
gravities. When the combining weight of any of these elements and
compounds is taken in pounds, then the gas or vapor therefrom will always
occupy about 377.07 cubic feet of space, at 60° Fahr. and 30 inches
barometer. If we divide this constant 377.07 by the combining weight of
any of the substances, then the quotient will be the number of cubic feet
per pound of the same. If we divide the combining weight of any of the
substances given in the table by 2, then the quotient will give the
density of the same, as compared with hydrogen. If we divide the combining
weight of any of the substances by the constant 28.87, then the quotient
will be the specific gravity of the gas or vapor therefrom, as compared
with air. All the calculations are based on the atomic weights which are
now generally adopted by the majority of chemists.

-------------------------------------------------------------------
| | |Cub. Ft.| |
| | | per | |
| Combi- |Cub. Ft.| Combi- |Specific|
| ning | per | ning |Gravity |
|Weight. | Pound. |Weight. |Air = 1.|
------------------------------+--------+--------+--------+--------|
Hydrogen (H_{2}) | 2.00 | 188.53 | 377.07 | 0.0692 |
Carbon vapour (C_{2}) | 23.94 | 15.75 | 377.07 | 0.8292 |