a 
PHYSICAL anv LITERARY. 195 
grains of this acid had been added. The 
 phial with its contents now weighed two 
ounces, four drams, and fifteen grains. 
One {cruple, therefore, and eight grains 
were loft during the ebullition, of which 
a trifling portion may be water, or fome- 
thing of the fame kind. The reit 4s air. . 
THE celebrated Homberg has attempted 
to eftimate the quantity of folid fale con- 
tained in a determined portion of the fe- 
eral acids. He faturated equal quanti- 
ties of an alkali with each of them; and, 
obferving the weight which the alkali had 
gained, after being perfe@ly dried, took 
this for the quantity of folid falt coatain- 
ed in that fhare of the acid which perform- 
ed the faturation. But we learn from the 
above experiment, that his eftimate was 
mot accurate; becaufe the alkali lofes 
weight as well as gains it. 
Two drams of magnefia, treated exact- 
dy as the alkali in the laft experiment, were 
_ juft diffolved by four drams, one fcruple, 
and feven grains of the fame acid liquor, 
and loft one fcruple and fixteen grains by 
ithe ebullition. 
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