"FLYING."


_To the Editor of the Scientific American:_

Your correspondent on this subject in the issue of April 14 cites an
array of facts from which it would seem the proper conclusions should
be inferred. I think the whole difficulty arises from a confusion of
terms, and by this I mean a want of care to explain the unknown
strictly in terms of the known; and I think underlying this error is a
misconception as to what an animal is, and what animal strength is,
only of course with reference to this particular discussion, i.e.,
in so far only as they may be considered physical organisms having no
reference to the intellectual or moral development, all of which lies
beyond the sphere of our discussion.

Purely with reference to the development of physical strength, which
alone is under consideration, any animal organism whatsoever must be
considered simply in the light of a machine.

A compound machine having two parts, first an arrangement of levers
and points of application of power, all of which is purely mechanical,
together with an arrangement of parts, designed, first, to convert
fuel or food into heat, and, secondly, to transform heat into force,
which is purely a chemical change in the first instance, and a
transformation of energy in the second. So much for the animal--man or
beast--as a machine physically considered.