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OR, THE PLAIN

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WHY AND BECAUSE.

FAMILIARIZING SUBJECTS OF USEFUL CURIOSITY AND

AMUSING RESEARCH.

BY JOHN TIMBS,
Editor of · Laconics :' Arcana of Science and Art,' &c.

“Its beginning is pleasure, its progress knowledge, and its objects truth

and utility.” -Sir Humphry Davy.

Zoological Series.

BOSTON:

LILLY & WAIT, AND CARTER & HENDEE.

NEW-YORK, E. BLISS; PHILADELPHIA, CAREY AND HART;

NEW ORLEANS, M. CARROL; PORTLAND, S. COLMAN.

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MECHANICS.

INTRODUCTORY.

Why are certain truths termed physical ?

Because they explain the greater part of the phenomena of nature, the term physical being derived from the Greek word signifying nature ; an appellation distinguishing them from chemical truths, which regard particular substances, and from vital truths, which have relation only to living bodies. Arnott.

Why is an atom so called ?

Because of its origin from a Greek word signifying that which cannot be farther divided; or, an exceedingly minute resisting particle.

Why is the term attraction used ?

Because the atoms of which the visible universe is built up, whether separate, or already joined into masses, tend towards all other masses, with force proportioned to their proximity: as, when any body presses or falls towards the great mass of the earth, or when the tides on the earth rise towards the moon.

Why is the term repulsion used ?

Because, under certain known circumstances, as of heat diffused among the particles, their mutual attraction is countervailed or resisted, and they tend to separate with force proportioned to their proximity : as, when heated water bursts into steam, or when gunpowder explodes.

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