dmit that the remedial power of motion,
transmitted either manually or mechanically, is founded upon rational
and physiological principles. All systems of medicine, however much they
may differ superficially, propose, as the chief end to be attained by
the administration of medicine, or by other treatment, that _motions_
identical with physiological activity should be incited or promoted. How
best to accomplish this result, and with least cost to vitality, is an
important consideration. Bearing in mind the conservation of forces,
that energy or power is as indestructible as matter, that it may be
changed into other forms but never lost, it is plain that mechanical
force may be applied to the living system and transformed into vital
energy; that chemical action, animal heat, and magnetism may represent
in the system the mechanical force transmitted to the body. Keeping in
view the transformable nature of force, and the need that our systems
have of auxiliary power in different departments, when normal activity
is impaired by disease, we can readily understand how undoubted,
curative effects result from either the manual or the mechanical
administration of motion.

RUBBING is a process universally employed by physicians of every school
for the relief of a great diversity of distressing symptoms, is
instinctively resorted to by sympathizers and attendants upon the sick,
and constitutes one of the chief duties of the nurse. Uncivilized people
resort to this process as their principal remedy in all forms of
disease.

The difficulty in administering motion as a remedial agent by manual
effort, such as rubbing, kneading, oscillating, flexing, and extending
the limbs, lies in the impossibility of supplying the _amount,
intensity_, and _variety_ of movement required to make it most
effective. The power of the arm and the strength of the operator are
exhausted before the desired effect is produced. Inventive genius has at
last overcome the obstacles to the successful and perfect administration
of motion as a curative agent. We have now a series of machines
propelled by mechanical power, by the use of which we rub, knead,
manipulate, and apply in succession a great variety of movements to all
parts of the body. These machines transmit motion to the body from
inexhaustible sources, never tire, but are ever ready for new, remedial
conquests. The movements administered by their use, _while entirely
under the control of the patient_