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tearing, some merely for cutting; all for one general purpose, but varying according to the manner of life natural to the animal. Muscles, in like manner, which are the agents of motion, are fitted in man and in beasts for walking or running, in birds for flying, in fish for swimming; the same in principle, but varying according to the wants of the particular being. Human anatomy and physiology will therefore give an idea of the structure and functions of animals.
The body of man, viewed apart from his immortal soul, may be considered as a frame-work consisting of bones, ligaments, muscles, and joints, for 'locomotion ;-organs to act on food, so that the body may be nourished ;vessels to carry this nourishing fluid to the parts requiring it ;-other vessels to take back the refuse or worn-out matter ;-and a nervous system, presiding over sensation and motion.
All these parts may be perfect, but to act they must have life. When any one or more parts of importance cease to be able to act,-for instance, if the stomach cannot digest, or if the heart cannot send the nourishment over the body,—then life cannot be kept up. Seeing this, we must be careful to know what each organ requires, and to treat it so that it may do its duty healthily. For instance, the stomach is made for a proper quantity of animal and vegetable food, not for strong spirits; consequently, though a few people may drink frequently of strong spirits, and continue to live, the common consequence is, that the stomach is injured, and the man dies sooner than he otherwise would.
In like manner, excess either in eating or drinking,— improper 'exposure to intense cold or heat,-filth,—vice, - bad air, and many other causes, by hindering the regular and healthy action of various organs, occasion disease and premature death.
. 1. Vide Root,
AFRICA. AFRICA is less known than any other portion of the globe. Many parts of the interior have never been visited by Europeans. The greater part of the inhabitants are negroes, of which there are many tribes. Some of these are intelligent, and live tolerably well, but the greater part are either in a • savage or a 8 barbarons state.
The climate being warm, they need little shelter or clothing. Their houses are therefore poor mud huts, or slight 'tenements made of leaves or branches of trees. Their dress is often but a single piece of cloth tied around the waist. They are, however, a cheerful race, and spend much of their time in various amusements.
Beside the negroes, there are several other races of Africans. The inhabitants from Egypt to Abyssinia appear to consist of the original Egyptian people, mixed with Turks, Arabs, and others. The people of the ‘Barbary states are the descendants of the ancient · Carthaginians, mingled with the Saracens who conquered the country, together with Turks and Arabs.
The immense desert of 6 Sahara, with all the adjacent regions, appears to be occupied by wandering tribes of Arabs, who move from place to place with their horses and camels, like the people of Arabia, for pasturage or plunder.
Africa may be considered as, on the whole, the least 'civilized portion of the earth. The people are mostly Mahometans, and one half of them are nearly in a savage state. The rest are in a barbarous condition.
1. Vide Root. 2. Savage state, live by hunting, fishing, or robbery; dress in skins, and live in the open air, or in miserable huts. 3. Barbarous, when they understand agriculture, the pasturing of cattle, and some of the mechanical arts, but have no books or written language. 4. These are Morocco, Tunis, Tripoli, and till lately Algiers, which the French have just subdued. 5. Carthago was founded by a colony froin Tyre, 1600 B.C. 6. 1600 miles long, and 800 broad.
7. Sierra Leone being the principal.
The central parts of Africa abound in wild animals, such as lions, panthers, leopards, elephants, rhinoceroses, zebras, and giraffes. The woods are filled with chattering monkeys, the thickets are infested with monstrous serpents, ostriches roam over the deserts, various kinds of antelopes and deer in vast herds graze upon the plains, hippopotami are seen in the lakes and rivers, and crocodiles abound in the stagnant waters. Wild birds of every hue meet the eye of the traveller in nearly all parts of the country.
There are ? English and French settlements on the western coast of Africa. There was formerly a Dutch settlement at the southern extremity of the continent, but the English have had possession of it since the year 1806. This is called Cape Town, and is situated at the Cape of Good Hope.
The natives of Africa are supposed to be descended from Noah's son Ham, who went thither and settled in Egypt after the building of the tower of Babel, this country being near the land of Shinar. The kingdom of Egypt is very ancient, and was founded by Menes, one of the children of Ham, 2188 B.C. In the Bible, he is called Mizraim.
GEOGRAPHICAL.–Area, 11,350,000 square miles.- Population one hundred millions.
till the 15th century.
......................A.D. 1496, Mungo Park penetrated to the centre of Africa ..................... 1795 Lander traced the Niger to the sea ................................
. ANIMAL PHYSIOLOGY. . . Bones, Ligaments; and Cartilage. .: We have said that the body is composed of various parts ; let us explain them.
Bone is that which gives the body shape and statutë: We could not stand upright but for the firmness of the bones of the leg and thigh and back-bờné. It is also useful to protéct important parts; thus the head consists of several bones, which are curiously notched, so as to fit closely and firmly one to another ; within these the brain is contained and protected. The ribs are sổ arranged as to give the upper part of the body a coñvenient shape, and to protect the heart and lungs which are inside. It is necessary that the most important organs should be preserved from accidents, else, even from slight accidents, we should be in constant danger of deadly injury.
Bone is a firm, hard substance, consisting chiefly of phosphate of lime and gristly or animal matter. It is, of course, shaped in such a way as to be most suitable to its situation. When intended for motion, it is round like a stick, but hollow within, in order that it may be light and yet strong. The arch is the best combination of lightness and strength, hence the bones of the head form an arch over the brain. The foot is also an arch of vast strength, but composed of many bones joined by elastic substance, to make it capable of movement. There are about 260 bones in the human skeleton, which wame is given to the bones of the body when they are all properly arranged.
But with bones only we should not be able to move, they would give only passive strength ; muscles are the agents by which bones are moved, and the elastic substance that keeps the bones connected with one another while moving, is called 'ligament.
Ligament is a whitish or yellow substance, so strong
that a bone will oftener break than a ligament tear, There are little pits or rough places in the bones, where these ligaments are fastened, or inserted, as it is called. There are also rough places, and pits, and little 'projections on bones, serving for attachments of muscles. The knee-joint may serve to illustrate ligament. We want there a great capacity for motion, but we want great strength also, consequently there are tough ligamentous strings funning from one bone to the other-in front, behind, on each side, and in the centre of the joint.
But 4 joint must not only have strength apd mere capacity of motion, it must nove very easily : consequently there is a slippery oily-like fluid, called synovia, which qozes into the joint from a gland, just as it is wanted. Still further to ' facilitate motion, the ends of bones are tipped with what is called cartįlage, a smooth, shining, and slippery substance. Now the joint is com: plete and easy of motion. . .
Joints are shaped according to the movement required ; some allow a very extended movement, as the shoulder joint, and the hip joint; such are called ball and socket joints. Some are mere hinge joints, having a backward and forward movement; such are the joints of the knee and the fingers.
But there is another use for ļigament and cartilage. If we jump down upon the heel we feel a very great shake, which hurts us, and which, if there was no con. trivance, would destroy us, by shaking violently the brain and other parts which will not bear it. By jumping on the fore part of the foot, we come down without any shake or jar. This is owing chiefly to the ligaments and cartilages between the bones of the feet, and to an India rubber-like substance between each of the twenty, four bones which forms the 'vertebral column or back-bone.