y to visualize the motions
of the air having one thousand separate tones, to present to the eye of
the mind the battling of the pulses, direct and reverberated, the
imagination retires baffled at the attempt;" and he might have added, the
shallowness and fallacy of the wave theory of sound was made apparent.
He, however, does express himself as follows: "Assuredly, no question of
science ever stood so much in need of revision as this of the
transmission of sound through the atmosphere. Slowly but surely we
mastered the question, and the further we advance, the more plainly it
appeared that our reputed knowledge regarding it was erroneous from
beginning to end."

Until physicists are willing to admit that the physical forces of nature
are objective things--actual entities, and not mere modes of motion--a
full and clear comprehension of the phenomena of nature will never be
revealed to them. The motion of all bodies, whether small or great, is
due to the entitative force stored up in them, and the energy they
exercise is in proportion to the stored-up force.

Tyndall says that "_heat itself_, its _essence and quiddity_, IS MOTION,
AND NOTHING ELSE." Surely, no scientist who considers what motion is can
admit such a fallacious statement, for motion is simply "position in
space changing;" it is a phenomenon, the result of the application of
entitative force to a body. It is no more an entity than shadow, which is
likewise a phenomenon. Motion, _per se_, is nothing and can do nothing in
physics. Matter and force are the two great entities of the
universe--both being objective things. Sound, heat, light, electricity,
etc., are different forms of manifestation of an all-pervading force
element--substantial, yet not material.

* * * * *

[NATURE.]

THE RELATION OF TABASHEER TO MINERAL SUBSTANCES.

Mr. Thiselton Dyer has rendered a great service, not only to botanists,
but also to physicists and mineralogists, by recalling attention to the
very interesting substance known as "tabasheer." As he truly states, very
little fresh information has been published on the subject during recent
years, a circumstance for which I can only account by the fact that
botanists may justly feel some doubt as to whether it belongs to the
vegetable kingdom, while mineralogists seem to have equal ground for
hesitation in accepting it as a member of the mineral kingdom.

It is very interesting to hear tha