Human Anatomy Simplified; In 3 Lects (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated.1854 Excerpt: ... THIRD LECTURE. Our present Lecture will be on THE FIVE SENSES, including a reference to those organs of the human body through which those senses operate. Although the Senses, properly speaking, are, like the Soul, immaterial, that is, not consisting of substance or matter, but of sensations excited in the mind by external objects, and in this respect not proper subjects of anatomy; yet as all their organs are material, the3r constitute a proper and important branch of anatomical knowledge. The number and names of the Senses are the five following: --Seeing, --Hearing, --Smelling, --Tasting, --and Feeling. These comprehend our whole sources of sensation and knowledge. Without them the mind could have no ideas. The great end of the Senses is to make us acquainted with external objects and their qualities, and our perception of these is accompanied with a belief that they exist, and are what they appear to be. We commence with I.--THE EYE, which is the Organ of Seeing. A.--Rays of light from all parts. B.--Cornea, through which they pass. (.'.--Crystalline lens, where they are refracted. DO.--Divergent rays, nerve. EE.--Retina, upon which the picture is formed. F.--Optic The Eye is a most beautiful and ingeniously constructed object. It may be compared, in its structure, to a telescope, the purpose of both being to collect the rays of light proceeding from the surface of bodies, and to bring those rays to a common centre, by means of a peculiar lens, or glass, into a focus, or given point; and thus to form a very fine image or picture of the object before them. The Eye may be said to consist of two parts, --the internal and the external, or the Eye itself, and that which surrounds it. The eyes are situated in two bony cavities, or sockets, named orbits, in which th..