Of all these organs of the senses you will learn more hereafter; meanwhile, I want you to understand that by means of these various sensory nerves, we are, so long as we are alive and awake, receiving impressions from the external world, sensations of touch, sensations of roughness and smoothness, of heat and cold, sensations of good and bad odours, sensations of tastes of various kinds, sensations of all manner of sounds, sensations of the colours and forms of things.
By our skin, by our nose, by our tongue and palate, by our ears, and above all by our eyes, impressions caused by the external world are for ever travelling up sensory nerves to the brain; thither come also impressions from within ourselves, telling us where our limbs are and what our muscles are doing. Within the brain these impressions become sensations. They stir the brain to action; and the brain, working on them and by them, through ways we know not of, governs the body as a conscious intelligent will.
NICHOLSON’S GEOLOGY.
Text-Book of Geology, for Schools and Colleges.
By H. Alleyne Nicholson, M. D., D. Sc., M. A., Ph. D.,
F. R. S. E., F. G. S., etc., Professor of Natural History
and Botany in University College, Toronto.
12mo. 266 pages. Price, $1.50.
This work is thoroughly adapted for the use of beginners. At the same time the subject is treated with such fulness as to render the work suitable for advanced classes, while it is intended to serve as an introduction to a larger work which is in course of preparation by the author.
NICHOLSON’S ZOOLOGY.
Text-Book of Zoology, for Schools and Colleges.
BY SAME AUTHOR AS ABOVE.
12mo. 353 pages. Price, $1.75.
In this volume much more space has been devoted, comparatively speaking, to the Invertebrate Animals, than has usually been the case in works of this nature: upon the belief that all teachings of Zoology should, where possible, be accompanied by practical work, while the young student is much more likely to busy himself practically with shells, insects, corals, and the like, than with the larger and less attainable Vertebrate Animals.