88 -
I C E .
R E M A R K S g n t h e
When Capt. J a m e s , J- wintered in Charleton’s Hie, the Tea froze
in-the middle o f -December 1631 : it remains therefore only to examine,
whether the ice formed in the fea muft neceffarily contain
■ briny particles.-And here I find myfelf in a very difagréeable dilemma,
for during the intenfe froft o f thé winter, in 177.6, two fets of
experiments were made on the freezing o f fea-water, and published
J, .contradicting one another almoft in'every material point.
T h e one by Mr. Edward Nairne F . R,, S. an ingenious and accurate
obferver.; the other by Dr. Higgins, who treads Ledtures on
Chemiftry and Natural Philofophy, and confequently muft be fup-:
pofed to be well acquainted with .the fubjedt. I will therefore ftill
venture to eonfider the queftion as undecided by thefe experiments,'
and' content myfelf with making a few obfefvations on them; -but
previoufly I beg leave to make this general remark, that thofe, who
are well acquainted with Mechanics,. Chemiftry, Natural Philo-
fqnhy and the various Arts which require , a nice obfervation o f .minute
.circumftances, need not be informed, that an experiment or
machine, fucceeds often very well, when made upon a fmaller fcale,
but will not anfwer i f undertaken at large; and vice verfa machines
and experiments executed upon .a fmall fcale will not produce the
"effedt,
- -j- Kiftoire des Voyages, yol. L V I I . edit, in 12mo. p. 421.
X Mr. N airne’s experiments are found in the Pbllof. Tranf. vol, LX V I . p. 1. and Dr,
m^ fecdnclfiipplc'inmt to 'the Probability ó f rcctcbhig 'tbc 'North-Pok. p. 121,, 142.
W A T E R and t h e O C E A N . 89
effedt, which they certainly have when made in a more enlarged
manner. A few years ago'an experiment made on the dying o f leaflet,
did not fucceed when undertaken on a fmall fcale, whereas ■ it produced
the defired effedt when tried at a dyer’s lioufe with the
large apparatusand it evidently confirms the above affertion, which
I think I have a right to-apply to the freezing offalt-wat'er. It is
therefore probable, that the ice formed in the ocean at- large, in a
higher latitude, and' in a more intenfe degree o f cold, whereof w e
have no. idea here; may become folid, and free from- any briny
particles, though a few experiments made by Dr. Higgins, in his
houfe, on the freezing o f fait-water produced only a loofe’/- fpun-gy
ice,'filled'with briny particles. ■:
T h e ice formed o f fea-water by Mr. Nairne, was very hard, 3;
inches long, and 2 inches in diameter; it follows from thence, that
the wafhing the outftde o f this ice in frelh water, could not affedt
the infide o f a hard piece o f ice. This ice when melted, yielded
frelh water, which was fpecifically lighter than wafer, which was
-a mixture o f rain and fnow water; and next in lightnefs to diftilled
water. Had the ice thus obtained;, not been frelh, the-refiduum of
the fea water, after this ice had been taken out, could'not have'been
fpecifically heavier than fea-water,' which however was the cafe
in Mr. Nairne’s experiment. It feems'therefore, in my opinion;
-evident from hence, that fait-water does freeze, and has no other
ICEï
N briny