5. Of additions to human power. With respect to the first of
these causes, the forces derived from wind, from water, and from
steam, present themselves to the mind of every one; these are, in
fact, additions to human power, and will be considered in a
future page: there are, however, other sources of its increase,
by which the animal force of the individual is itself made to act
with far greater than its unassisted power; and to these we shall
at present confine our observations.

The construction of palaces, of temples, and of tombs, seems
to have occupied the earliest attention of nations just entering
on the career of civilization; and the enormous blocks of stone
moved from their native repositories to minister to the grandeur
or piety of the builders, have remained to excite the
astonishment of their posterity, long after the purposes of many
of these records, as well as the names of their founders, have
been forgotten. The different degrees of force necessary to move
these ponderous masses, will have varied according to the
mechanical knowledge of the people employed in their transport;
and that the extent of power required for this purpose is widely
different under different circumstances, will appear from the
following experiment, which is related by M. Rondelet, Sur L'Art
de Batir. A block of squared stone was taken for the subject of
experiment:

1. Weight of stone 1080 lbs

2. In order to drag this stone along the floor of the quarry,
roughly chiselled, it required a force equal to 758 lbs