[ 219 ] 
but he feems only to fpeak of it as a far lefs efilca- 
cious anti-feptic than fugar ; at leaf:, the honour of 
afcertaining the proportion in which it adts as a feptic 
undoubtedly belongs to Sir John Pringle; for Beecher, 
in his Phyjica Subterraneay lib, I. Je 5 l, v. cap. i. 
where he is fpeaking of this matter, fays, “ quod 
nimius falls ufus corpus putrefeere faciat, licut 
modicus a putredine praefervat.” 
To a table exhibiting the relative powers of neutral 
falts in refifling congelation, another might be ufe- 
fully added, denoting the powers of all the known 
acids and alkalies when diluted to a given denfity; 
as alfo of vinous fpirits, from highly redtified fpirits 
of wine to water impregnated with the minutefl 
quantity of fpirit. Not but that it may be con- 
jedtured a priori, that in this laft cafe the refifiiance 
to congelation would be diredly as the quantity of 
fpirit contained in given quantities of water. I made 
an experiment of this kind with fea fait; in equal 
quantities of water were diflblved quantities of fea 
fait, increafing in the arithmetical progreflion, o, 5, 
10, 15, 20, 6cc. ; the times in which the folutions 
began to freeze, reckoning from the time in which 
fimple water began, increafed accurately in the fame 
progreffion : hence it may be inferred, that, in fait of 
the fame kind, the refinance to congelation is in 
the dired fimple proportion of the quantity of fait 
diflblved; this conclufion cannot be extended to falts 
of different kinds, fince water faturated with fea fait is 
more difficultly congealed than when faturated with 
various other falts, which it difiblves in greater 
quantities. 
F 2 
Thefc 
