YOUTH-MATURITY.

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thirty years, and his life is proportionately long, being three score years and ten-seventy years-when he takes care of himself; but some of the lower animals attain their full size and growth in a few years, and scarcely ever live over twenty or thirty.

30. In early youth, before the body is matured, the functions of digestion, nutrition, etc., are very active, and are rapidly performed. The brain is larger, and the nervous system is then more developed than in after periods of life. The child eats, his food nourishes his body, and he grows rapidly; but the man eats a much greater quantity of food, yet we can scarcely perceive any difference in his stature or size from one year to another.

31. There is a period when the body has attained its full growth, called maturity. When this period is reached, there appears for a little time to be neither progress nor decline. Though there is in our system a power to repair all injuries which the body receives, to heal all the wounds, and to unite all the bones; yet the body will finally decay, regardless of all our exertions to guard and preserve it.

32. We cannot see that this decay is necessary from the nature of the body, neither can it arise from the gratification of the artificial wants of civilized life; for savages do not retain their faculties as long as those who are in a civilized state. But it appears to be the

30. In what condition are all the functions in youth? What is said of the brain and nervous system at that period? What is the effect of the food? Has the food the same effect on the man? 31. What is meant by maturity? What is the condition of the body at this time? Is there anything in our systems to enable us to resist injuries, etc.? Will this power always continue? 32. Do we know the causes of decay? What appears to be one cause?

order of nature, that man should live, then die. When adult life has passed, then the organs begin to decay.

33. The nervous system is first affected; the hearing, sight, etc., grow feeble; the muscles become stiff, hardened, and difficult to contract, so that they cannot well support the body; hence old persons are inclined to stoop and totter, and therefore require the additional assistance of a cane or staff. Then the circulating system begins to decline; bony substances gather around the veins and arteries, and thus interrupt the free passage of the blood. The lungs cannot breathe or inhale the air so well, therefore the blood is not so well purified.

34. These systems become more feeble, till they are no longer able to perform their various offices; then death ensues. Many accidents are fatal, and produce death in aged persons, because their bodies become enfeebled, and can neither assist nor repair injuries as well as in youth. The bones of children easily unite; but in after years there is a want of that strength and vigor, so that when the bones are shattered or injured, the injury cannot well be repaired.

35. Children, I hope by these few lessons and instructions, you will have been incited to think more of the functions of your bodies, and that the older you grow the more you will become interested in this important study. When you see flies walking and balancing themselves on the ceiling, think, and try to find out why they can support themselves there without falling. So

32. What takes place after adult life has passed? 33. What system is first affected? Why do aged persons require an artificial support? What system next decays? How does this affect the blood? 34. When does death ensue? Why are accidents more fatal to the aged than to the young? What is said in regard to the bones of children? 35. What ought these lessons to incite and encourage in children?

OBSERVATION-REASON.

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of everything around you. Be not contented to know that things are as you see them, but find out the reason for the different action, if you can. I hope you will now understand better than you did what physiology

means.

30. I will give you another chapter on the instincts of animals, and will then leave this interesting part of the subject, to speak of another part even more interesting, if possible: viz., the brain and nervous system.

35. Should the mind be contented by observation alone? What should we always endeavor to ascertain? 36. What subject will be next explained?

CHAPTER VI.

INSTINCT.

1. THERE is in many respects a great resemblance or analogy between man and other animals. Some animals exhibit marks of skill, sagacity, caution, or judgment; and, in many cases, the power of reasoning almost equal to human beings.

2. Some suppose that every animal possesses all the faculties with which man is endowed, only in a much more limited degree, modified by circumstances, but not guided by reason.

3. Whether this be correct or not, we know that animals show as many of these different talents as it is possible without having the intellect of man. Sometimes they appear to be guided by experience, observation, and even reason. However this may be, they are endowed with a principle that enables them to seek their food, build their habitations, and take care of their young, which is called INSTINCT. They have also the power to vary their means or course of action, in order to accomplish certain ends, when circumstances vary or require this change.

What is the subject of chapter sixth? 1. Is there any resemblance between man and other animals? What do some animals exhibit? 2. What is the opinion of some with regard to the faculties of man and human beings? 3. What certain knowledge have we respecting them? By what do they appear to be guided? With what are they endowed? What is this principle called? When can they vary their means of

action?

DIFFERENT KINDS OF INSTINCTS.

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4. Instinct is that which prompts an animal to act, without teaching from others; to follow a certain course which is best adapted to his wants and condition.

5. The reason of man has been called a "bundle of instincts;" yet there is a wide difference between the powers of men and animals. Man improves from one year to another; his knowledge is the result of experience, observation, and reflection.

6. The dwellings of man differ in different countries and ages, from the hut of the savage to the palace of the king; though man constructed both the hut and the palace.

Beavers build the same kind of houses now that they built many hundred years ago; and so of all other animals; there is no improvement from one generation to another; they always continue the same.

7. Smellie says there are two kinds of instincts; one kind which the animal can scarcely help obeying, without any instruction or experience; and a second kind by which they can accommodate themselves to peculiar situations, and can also improve by experience and observation.

8. I will relate some anecdotes to you, which illustrate these different instincts in some of the different animals; and though it may seem to you impossible that these are true, yet I shall mention none except those

4. What is instinct? 5. What has the reason of man been called? What difference is there between the powers of men and animals? 6. What is said of the dwellings of man in different ages? What is said of the houses of beavers in different ages ? 7. How many kinds of instinct are there? What is the first kind? What is the second kind? 8. How can these different instincts be illustrated?