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ANATOMY, &c.

1. Anatomy is the science which treats of the structure and relations of the different parts of animals and plants.

2. It is divided into Vegetable and Animal anatomy. The latter of these divisions is subdivided into Human anatomy, which considers, exclusively, human beings; and Comparative anatomy, which treats of the mechanism of the lower orders of animals.

3. Physiology treats of the functions, or uses of the organs of animals and plants. Another definition is, “the science of life.”

4. This is also divided into Vegetable and Animal physiology, as it treats of the vegetable or animal kingdom; and into Human and Comparative physiology, as it describes the vital functions of man or the inferior animals.

5. Hygiene is the art or science of maintaining health, or a knowledge of those laws by which health may be preserved.

6. The kingdom of nature is divided into organic and inorganic bodies. Organic bodies possess organs, on whose 14 action depend their growth and perfection. This division includes animals and plants. Inorganic bodies are devoid of organs, or instruments of life. In this division are classed the earths, metals, and other minerals.

1. What is anatomy? 2. How is it divided? How is the latter division subdivided? 3. What is physiology? Give another definition. 4. How is physiology divided? Give a subdivision. 5. What is hygiene? 6. Define organic bodies.

7. In general, organic matter differs so materially from inorganic, that the one can readily be distinguished from the other. In the organic world, every individual of necessity springs from some parent, or immediate producing agent; for while inorganic substances are formed by chemical laws alone, we see no case of an animal or plant coming into existence by accident or chance, or chemical operations.

8. Animals and plants are supported by means of nourishment, and die without it. They also increase in size by the addition of new particles of matter to all parts of their substances; while rocks and minerals grow only by additions to their surfaces.

9. “Organized bodies always present a combination of both solids and fluids;—of solids, differing in character and properties, arranged into organs, and these endowed with functional powers, and so associated as to form of the whole a single system;—and of fluids, contained in these organs, and holding such relation to the solids that the existence, nature, and properties of both mutually and necessarily depend on each other.”

10. Another characteristic is, that organic substances have a certain order of parts. For example, plants possess organs to gain nourishment from the soil and atmosphere, and the power to give strength and increase to all their parts. And animals need not only a digesting and circulating apparatus, but organs for breathing, a nervous system, &c.

6. Define inorganic bodies. 7. What is said of the difference, in general, between organic and inorganic bodies? 8. What of the growth of organic and inorganic bodies? 9. What do organized bodies always present? 10. Give another characteristic of organized substances.

11. Individuality is an important characteristic. For instance, a large rock may be broken into a number of smaller pieces, and yet every fragment will be rock; but if an organic substance be separated into two or more divisions, neither of them can be considered an individual. Closely associated with this is the power of life, or vitality, which is the most distinguishing characteristic of organic structure; since we find nothing similar to this in the inorganic creation.

12. The distinction between plants and animals is also of much importance. Animals grow proportionally in all directions, while plants grow upwards and downwards from a collet only. The food of animals is organic, while that of plants is inorganic; the latter feeding entirely upon the elements of the soil and atmosphere, while the former subsist upon the products of the animal and vegetable kingdoms. The size of the vegetable is in most cases limited only by the duration of existence, as a tree continues to put forth new branches during each period of its life, while the animal, at a certain time of life, attains the average size of its species.

13. One of the most important distinctions between animals and plants, is the different effects of respiration. Animals consume the oxygen of the atmosphere, and give off carbonic acid; while plants take up the carbonic acid, and restore to animals the oxygen, thus affording an admirable example of the principle of compensation in nature.

14. But the decisive distinctions between animals and plants are sensation and voluntary motion, the power of acquiring a knowledge of external objects through the senses, and the ability to move from place to place at will. These 16 are the characteristics which, in their fullest development in man, show intellect and reasoning powers, and thereby in a greater degree exhibit to us the wisdom and goodness of the Creator.

11. What is said of the individuality of organized and inorganized bodies? What is