Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER II. THE FUNDAMENTAL PHYSIOLOGICAL ACTIONS. The Properties of the Living Body. When we turn from the structure and composition of the living Body to consider its powers and properties we meet again with great variety and complexity, the most superficial examination being sufficient to show that its parts are endowed with very different faculties. Light falling on the eye arouses in us a sensation of sight, but falling on the skin has no such effect; pinching the skin causes pain, but pinching a hair or a nail does not; when the ears are stopped, sounds arouse in us no sensation; we readily recognize, too, hard parts formed for support, joints to admit of movements, apertures to receive food and others to get rid of waste. We thus perceive that different organs of our Bodies have very different endowments and serve for very distinct purposes; and here also the study of internal organs shows us that the varieties of quality observed on the exterior are but slight indications of differences of property which pervade the whole, being sometimes dependent on the specific characters of the tissues concerned and sometimes upon the manner in which these are combined to form various organs. Some tissues are solid, rigid and of constant shape, as those composing the bones and teeth; others, as the muscles, are soft and capable of changing their forms; and still others are capable of working chemical changes by which such peculiar fluids as the bile and the saliva are produced. We find elsewhere a number of tissues combined to form a tube adapted to receive food and carry it through the Body for digestion, and again similar tissues differently arranged to receive the air which we breathe- in, and expel it after abstracting part of its oxygen and adding to it certain other things;... --This text refers to the Paperback edition.