252 Scientific Intelligence. 
of which were placed thermometers showing zAoth degree ; the time 
of fusion in the calorimeter on the average about 12 mi 
stant setting out from a temperature of —2°, and was then represented 
From this it may be inferred that ice approaches very near 
its point of fusion without sensibly changing its consistence, the slight 
softening which precedes the fusion being comprised within an in- 
terval of 2 degrees: the passage of ice from a solid to a liquid state 
though sufficiently well defined is still effected by degrees and not ab- 
ruptly. It will be remembered that De la Provostaye and Dessains on 
the one hand, and Regnault on the other, had found for the latent heat 
of ice the number 79; the experiments of Regnault had however clearly 
shown that this number was not constant but increased as the initial 
temperature of the ice diminished at least as far as —0°61, for which 
the corresponding latent heat was 79°71.—Ann. de Chimie et de Phys- 
ique, Sept., 1850. 
2. Liquefaction of Gases.—Bertuetor has applied the expansive 
force of heated liquids to the liquefaction of gases upon a small scale. 
A thick glass tube having a small bore is to be sealed at one end and 
then filled with pure and dry mercury free from air; the open end of 
the tube is then to be drawn out to a capillary orifice, without diminish- 
ing the ratio between the thickness and the interior diameter of the 
tube. The column of mercury is then to be heated in a water bath 
eye. The author suggests the employment of the gas or solar micro- 
pe é 
that Light always appears at the negative pole, and that this Aig 
is properly the positive pole, and that this heat is originally dark heat, 
3d, that Light and Heat do not unite in the instant of evolution but — 
only after the intensity of each has reached a certain point ; from this 
ha already become very hot. The experiments were subsequently 
repeated in Paris by means of an apparatus contrived by Duboscq 10 
