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Classification of the Sci.
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applied by converting it into elasticity, as in the Steam Engine. The subdivisions of such engines are well known and need nowhere be further noticed. Smoke jacks apply heat in another way.

d. By Galvanism.

e. By Meteorological forces, as Wind, the Sun's heat, tidal action, etc.

f. By biological forces, as when horses, mules, and oxen, dogs, and human beings are emplyed as prime motors.

B. The Materioperous Sciences divide themselves into.

i. Sciences of operations upon the Surfaces of bodies.

ii. Sciences of operations depending on the texture and structure of materials.

iii. Groups of sciences whose unity lies in the general form to be given to the matter.

i. Sciences concerned with operations upon the Surfaces of bodies include

1. Sciences of cleansing; a, of Hard surfaces; b, of yielding surfaces