" He also adds, that what was afterwards called the Egyptian
science, the Hermetic art, the art of transmuting metals, was a mere
reverie of the middle ages, utterly unknown to antiquity. "The pretended
books of Hermes are evidently supposititious, and were written by the
Greeks of the lower Empire."
Crystallization.
Why are the crystals collected in camphor bottles in druggists' windows
always most copious upon the surface exposed to the light?
Because the presence of light considerably influences the process of
crystallization. Again, if we place a solution of nitre in a room which
has the light admitted only through a small hole in the window-shutter,
crystals will form most abundantly upon the side of the basin exposed to
the aperture through which the light enters, and often the whole mass of
crystals will turn towards it.--Brande.
Why is sugar-candy crystallized on strings, and verdigris on sticks?
Because crystallization is accelerated by introducing into the solution
a nucleus, or solid body, (like the string or stick) upon which the
process begins.
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