109
OF FRIGORIFIC MATTER.
committed by using bad ones, or by the want of skill to ufe them
properly. But the truth is, that in the facts adduced by Muschen
broeck, no thermometer whatever was applied to the water itself, but
only vague reasoning is employed, to make it appear probable that it
was not cooled to the proper degree. We may, therefore, pass over
the greater number of his reasons, and take some notice of a few only
of his facts, which are surprising in themselves, and could not be ex
plained by any principles then known, and which besides are stated
by him in such a manner as to make them appear uncommonly per
plexing.
The fact which first induced him to think that ice is formed by the
entrance of extraneous matter into water, is the enlargement of bulk ;
ice being always more bulky than the water from which it was pro
duced, in the proportion of about 9 to 8. This enlargement of bulk
is the effect of a powerful cause acting with great force, which has
been ſhewn by many experiments. “ Now he thinks it more proba
“ ble that this enlargement of bulk, and the force with which it is
“ performed, depend on the entrance of some subtile matter, than on
“ the simple diminution of heat, the general effect of which is to oc
“ casion contraction in bodies.
To the whole of this argument, however, it is eaſy to answer, that
the fact is better explained by the supposition of a particular modifi
cation of the attraction, which makes the parts of the water unite and
cohere, in one way rather than in any other.
The attraction of cohesion, which, in this case, is the attraction of the
particles of the water for one another, is undoubtedly the cause of the
concretion of water into ice, as it is the cause of the solidity and hard
ness of all other bodies. No person doubts that the hardness of iron
is owing to the cohesive attraction of its particles for one another.
We can make these particles change their position among one ano
ther, by hammering the iron, or drawing it into wire, and they still
cohere. And yet, when iron that has been melted is allowed, by cool¬