14
THE THEORY OF SCREWS.
[8
If it be objected, that with so great a restriction as that just referred to,
only a limited field of inquiry remains, the answer is as followsA perfectly
general investigation could yield but a slender harvest of interesting or
valuable results. All the problems of Physical importance are special cases
of the general question. Thus, a special character m the constraints has pro-
duced the celebrated problem of the rotation of a rigid body about a fixed
point. To vindicate our particular restriction it seems only necessary to
remark, that the restricted inquiry still includes the theory of Equilibrium,
of Impulsive Forces, and of Small Oscillations.
Whatever novelty may be found in the following pages will, it is
believed, be largely due to the circumstance that, with the important
exception referred to, all the conditions of each problem are of absolute
generality.