On the 11th of January 1774, a young stu-
dent of physic at Goettingen, about half an
hour after five o’clock in the afternoon, put
three drams of quicksilver into a small open glass.
Upon this, he laid some loose snow and sal am-
moniac, mixed in equal parts. This he put out
at a window, from the third floor of a house,
by which it was expoed to the open air from the
north-west. And he, at the same time, mixed
with the snow upon which the glass stood, about
two drams of sal ammoniac.

The snow and salt were soon congealed; but,
on the mercury no alteration was perceived, till
about one o’clock in the morning; Mr Blumen-
bach then found that the quicksilver was become
solid. He observed, that it was divided into fix
pieces, two were large ones, of more than a
dram each. One of them had a hemispherical
shape, the other cylindrical. The four others of
a smaller size, were nearly about half a scruple
each. They were all with a flat side, frozen fast
to the glals, but not in contact with the snow and
sal ammoniac, with which it was covered.
Their colour was different from that of mercury
in its liquid state; it was pale, without any gloss,
[Seite 109] and tended a little to a blue colour, somewhat
resembling zinc.

Mr Blumenbach would have broken the glass
to try how they did under the hammer; but he
wished rather to have witnesses of this curious
phaenomenon. At this time, Fahrenheit’s ther-
mometer stood ten degrees under 0. In the
morning, about seven o’clock, he observed, that
the hemispherical piece began to melt, perhaps
from its being more exposed to the open air, and
from its being farther removed from the mixture
with sal ammoniac under the glass than the rest.
It had then the appearance of an amalgama, tend-
ing a little to that side to which Mr Blumenbach
inclined the glass. The other five pieces still re-
mained solid; and he now called for several of
his fellow students, whose names he mentions,
and who observed, along with him, this extraor-
dinary occurrence. About eight o’clock, the
cylindrical piece began to melt; and soon after
the four smaller pieces shared the same fate. They
dissolved into small bright globules, and soon dis-
appeared in the interstices of the congealed snow
and sal ammoniac.