1 66 Mr. Schmeisser's Description of an Instrument 
found either the least difference in the results, or any thing 
else contrary to my expectations. 
The manner of using this instrument, and preparing it for 
experiments, is as follows. 
(1.) A. An accurate cubic inch, which is fastened, by 
means of a horse-hair, to a hydrostatic balance, is to be sus- 
pended in a vessel with distilled water, of the temperature of 
6 o degrees, according to Fahrenheit ; when the sum of the 
weight which the cubic inch thus loses, in the water, will be 
equal to the weight of an equal quantity of water displaced 
by it. 
(2.) B. The instrument, free from moisture, is then to 
be put into the scale of an accurate balance, and its weight 
ascertained, from which the weight of the common air con- 
tained in the bottle must be deducted ; when the remainder 
will indicate the absolute weight of the instrument. 
(3.) C. The bottle of the apparatus is then to be filled 
with distilled water, of the temperature of 60 degrees, and 
the stopper, with the thermometer, fitted to the bottle, so that 
neither the smallest bubble of air may remain in it, nor any 
of the fluid adhere to the outside of the stopper or bottle ; 
after which the weight of the water is to be ascertained, and 
marked upon the bottle, from which, by calculation accord- 
ing to experiment A, the quantity of water, contained in the 
bottle in cubic inches measure, may be found. Having thus as- 
certained the quantity of water of bo degrees of temperature 
which the bottle contains, the bottle may then be filled with 
any other fluid of the same temperature, and its weight as- 
certained, according to experiment C, and compared with 
that of distilled water. If, for example, the bottle be found 
