M. Amagat has succeeded in solidifying various liquids, by compressing
them in cylinders of bronze and steel. He has also photographed the
crystals after crystallization, by means of a ray of electric light
traversing the interior of the vessel by glass cones serving as panes.
The stages of crystallization can be observed in this way with
chloride of carbon, and it is seen that the process varies with the
rapidity with which the pressure is produced. If rapidly, a sudden
circlet of crystals gathers round the edge of the luminous field, and
grows to the center. The pressure being continued, the field becomes
obscure, then transparent. As the pressure is diminished the reverse
takes place, and the liquid state is reproduced. M. Amagat finds that
chloride of carbon solidifies at 19.5° Cent., under a pressure of 210
atmospheres. At 22° Cent., benzine crystallizes with a pressure of
about 900 atmospheres.
* * * * *
THE
SCIENTIFIC AMERICAN SUPPLEMENT.