of Sea lVater y ifc, 47 
alkali were added, and the fame appearances 
occurred. 
EXPERIMENT VII. 
Each of thefe precipitates were rapidly and 
wholly diffolved, the greateft part of the water 
being firft poured off, on the addition of a few 
drops of dilute vitriolic acid. A proof that the 
precipitated earth was magnefia. 
EXPERIMENT VIII. 
To determine whether the addition of a por¬ 
tion of bitter purging fait, to a folution of com¬ 
mon fair, would prevent the forming of lime 
water, with an equal quantity of lime to that 
which had preferved the fea water, I mixed 
twenty grains of quicklime, feven drachms of 
common fait, and one drachm of bitter purging 
fait with a pint of rain water j but no lime water 
was produced. Whereas, a lime water was 
formed, by an equal quantity of lime with a pint 
of rain water, and alfo with a folution of common 
fait, from which the earthy matter it contained 
had been previoufly precipitated by fofTil alkali, 
and the alkali neutralifed by marine acid. 
The next queftion that prefented itfelf to my 
investigation, w'as, whether the common Chefhire 
fait w'as fo impregnated with magnefian fait, 
as to prevent the forming lime water, with a like 
quantity of lime, when ufed in the proportion 
of an ounce of fait to a pint of water. 
E X P E- 
