There seems to be no limit to the
possibilities of high explosives when intelligently applied to the
warfare of the future, and the advantage will always be on the side of
the nation that is best prepared to use them.
* * * * *
THE MANUFACTURE AND USE OF PLASTER OF PARIS.
It has long been a familiar fact that gypsum yields on baking a
material which possesses the power of setting with water to a firm
mass, this setting being accomplished much more quickly than is the
case with mortar.
The explanation of the setting of plaster was first given by
Lavoisier, who pointed out that gypsum is an hydrated salt, and that
the set plaster is in fact gypsum reformed, the change brought about
by baking being merely loss of water of crystallization. The beds of
gypsum of most importance both formerly and at the present time in the
plaster manufacture occur in the neighborhood of Paris in the lower
tertiary formation. Different beds differ (1) in respect of character
and quantity of admixed materials and (2) in the structure of the
gypsum itself. With regard to the first point, some deposits contain a
notable proportion of carbonate of lime, a fact which under certain
circumstances may considerably influence the character of the plaster.
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