into corresponding Expression o? Specific Gravity . §& 
tares of ale olio! and water of different densities. In this 
hydrometer the zero is placed not at the point to which 
the stem sinks in distilled water, but at the point to 
which it falls in a mixture of 10 parts of salt and 90 of 
water. The interval between this point and that of dis- 
tilled water is marked on the scale as 10 degrees, and 
this scale is continued upwards on the stem simply hy 
measuring equal portions by the compasses. The 10th 
degree of the spirit hydrometer corresponds with the 0, 
of the salt hydrometer, and it is certainly a defect that th& 
ingenious inventor should have introduced this deviation 
from what is obviously the natural zero in each scale,, 
namely, the point of immersion in distilled water ; since 
it was as easy to obtain a measure for 10 degrees of the 
scale of the spirit hydrometer by beginning the notation 
10 degrees below zero as at this point. 
The correspondence between Beaume’s spirit hydro* 
meter and the real expression of specific gravity has also 
been calculated by Mr. Nicholson, and on the following 
data : viz. Beaume found that a spirit of .842 sp. gr. afc 
82° Fahr. gave 37 degrees of his hydrometer; and that 
a mixture of two parts, by weight, of this spirit with 3d 
of water gave 12 degrees of the hydrometer at the same- 
temperature. 
This mixture is found by Gilpin’s valuable tables to 
be = .9915 specific gravity at this temperature, and 
these terms, viz. .842 and .9915 become .832 and .990^ 
at 55° Fahr. or 10 s Ileaum. the standard temperature of 
the graduation of these instruments. We have given in 
^he article Alcohol, p. 30, Yol. i, * of this work, Beau- 
me’s table of the density of different mixtures of alcohol 
and water expressed in the degrees of his hydrometer^ 
with the corresponding specific gravities as given by 
Yol. r. 
'Of Aik in’s Dictionary. EnV 
51 
