When water
is converted into steam, the distances between the molecules are greatly
augmented, but the molecules themselves continue intact. We must not,
however, picture the constituent atoms of any molecule as held so
rigidly together as to render intestine motion impossible. The
interlocked atoms have still liberty of vibration, which may, under
certain circumstances, become so intense as to shake the molecule
asunder. Most molecules--probably all--are wrecked by intense heat, or
in other words by intense vibratory motion; and many are wrecked by a
very moderate heat of the proper quality. Indeed, a weak force, which
bears a suitable relation to the constitution of the molecule, can, by
timely savings and accumulations, accomplish what a strong force out of
relation fails to achieve.
We have here a glimpse of the world in which the physical philosopher
for the most part resides. Science has been defined as "organized common
sense;" by whom I have forgotten; but, unless we stretch unduly the
definition of common sense, I think it is hardly applicable to this
world of molecules. I should be inclined to ascribe the creation of that
world to inspiration rather than to what is currently known as common
sense. For the natural history sciences the definition may stand--hardly
for the physical and mathematical sciences.
The sensation of light is produced by a succession of waves which strike
the retina in periodic intervals; and such waves, impinging on the
molecules of bodies, agitate their constituent atoms.
Pages:
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105