for ascertaining the specific Gravities of Fluids. 167 
to contain 327 grains of distilled water, and 654 of another 
fluid, the difference will be as 1 to 2 ; or 654 divided by 
327, will give 2 for the quotient. The specific gravity then, 
of the fluid thus found, compared with that of distilled water, 
is properly expressed by the ratio 2,000 : 1,000 ; which latter 
expression is taken for the standard. 
As ft is a known fact that fluids exhibit different specific 
gravities at different temperatures, it would have been ne- 
cessary for me to form a table, exhibiting the specific gra- 
vities of fluids at different temperatures, had I not, in order 
to avoid this inconvenience, hit upon a method of bringing the 
fluids, whose specific gravities are to be investigated, to a cer- 
tain standard, viz. to 60 degrees, by setting the bottle with 
the fluid in a glass vessel with cold water, and adding as 
much warm water as may be necessary to bring that fluid to 
this standard of 60 degrees. 
As the fluor acid will in some measure dissolve the glass, 
it becomes necessary, when that acid is to be weighed, to coat 
the inside of the bottle, by melting a little bees-wax in the 
bottle, and turning it, with the thermometer, in such a man- 
ner that the inside, together with the lower part of the ther- 
mometer, may become totally covered when cooled ; which 
coating may easily be removed by means of a little oil of 
turpentine, or any other essential oil, all of which dissolve 
wax very readily. 
