most substances to the fluid state; while the greatest number of
_liquid_ substances take a _solid_ form by the loss of caloric. Thus,
water congeals and forms ice; and even the gases show this disposition
to become solid, when they lose their _elasticity_ by forming some
_combination_.


Explain the terms _Repulsion_ and _Attraction_.

Repulsion is a peculiar property in the particles of matter, which
gives them a constant tendency to recede from each other. Attraction
is an unknown force, which causes bodies or their particles to
approach each other. The particles of all bodies possess this
property, which causes them to adhere, and preserves the various
substances around us from falling in pieces.


What different kinds of Attraction can you mention?

Attraction may be distinguished into that which takes place between
bodies at sensible distances, and that which manifests itself between
the _particles_ of matter at insensible distances.


Give an example of the first kind of attraction.

One of the most familiar instances of attraction at sensible distances
is seen in the descent of heavy bodies to the ground. When a stone is
lifted up in the hand, the earth's attraction, which previously caused
it to remain at its surface, is overcome; but, as soon as the hand is