atoms are never still. Masses of matter may be
still, but not the constituent elements. They are always in intensest
activity, like a mass of bees--those inside coming out, outside ones
going in--but the mass remains the same.

The atoms of water behave extraordinarily. I know of a boiler and
pipes for heating a house. When the fire was applied and the
temperature was changed from that of the street to two hundred degrees,
it was easy to see that there was a whole barrel more of it than when
it was let into the boiler. It had been swollen by the heat, but it
was nothing but water.

Mobile, flexible, and yielding as water seems to be, it has an
obstinacy quite remarkable. It was for a long time supposed to be
absolutely incompressible. It is nearly so. A pressure that would
reduce air to one hundredth of its bulk would not discernibly affect
water. Put a ton weight on a cubic inch of water; it does not flinch
nor perceptibly shrink, yet the atoms of water do not fill the space
they occupy. They object to being crowded. They make no objection to
having other matter come in and possess the space unoccupied by them.

Air so much enjoys its free, agile state, leaping over hills and
plains, kissing a thousand flowers, that it greatly objects to being
condensed to a liquid. First we must take away all the heat. Two
hundred and ten degrees of heat changes water to steam filling 1,728
times as much space. No amount of pressure will condense steam to
water unless the heat is removed. So take heat away from air till it
is more than two hundred degrees below zero, and then a pressure of
about two hundred atmospheres (14.7 pounds each) changes common air to
fluid. It fights desperately against condensation, growing hot with
the effort, and it maintains its resilience for years at any point of
pressure short of the final surrender that gives up to become liquid.

Perhaps sometime we shall have the pure air of the mountains or the sea
condensed to fluid and sold by the quart to the dwellers in the city,
to be expanded into air once more.

The marvel is not greater that gas is able to sustain itself under the
awful pressure with its particles in extreme dispersion, than that what
we call solids should have their molecules in a mazy dance and yet keep
their strength.

Since this world, in power, fineness, finish, beauty, and adaptations,
not only surpasses our accomplishment, but also is past our finding out
to i