[ »49 3 
Experiment XIV. 
Monf. Geojfroy^ a celebrated Member of the Aca- 
demy of Sciences, looks on it as a lingular Power 
of common Salt Ammoniac, that being mixed with 
a certain Quantity of Water, it rendered the Water 
fo cold, that it made the Spirit of his Thermometer, 
eighteen Inches high, fall thirty-three Lines. But I 
have fhewn to feveral Perfons, that the Vefuvian Salt 
makes the Liquor of a Thermometer, like his, fall 
four Inches and an half; which is equal to fifty-four 
Lines. Wherefore the Efficacy of this Salt, in caufing 
the Fall of the Liquor, exceeds the Efficacy of com- 
mon Salt Ammoniac by twenty-one Lines. 
Experiment XV. 
If round a VefTel full of Water cooled with Snow, 
there be put fome 6f the Salt of Vefuvius^ the Water, 
freezes and grows hard in a very little time. 
Experiment XVI. 
If you put a good Quantity of the Salt of Vefuvim 
into Snow fet round a [Glafs] VefTel full of Water, 
and then ftir the VefTel, the Water contained therein 
becomes unfit to drink ; having acquired a very dif- 
agreeable acrid fulphureous Taflc ; a manifefl Sign, 
that the Salt is divided into fmall Particles, which 
paffing through the infenfible Pores of the Glafs,, 
enter into and mix with the Water. 
Experiment XVII. 
Of all kinds of Salts, this diflolves in the greateft 
Quantity in Water; and perhaps the greater or Idler 
DiT- 
