that all the cells can be similar without losing room. And, for the same intention, the planes of which the bottom is composed, if there be more than one, must be three in number, and neither more nor fewer.

It has been demonstrated, that, by making the bottoms of the cells to consist of three planes meeting in a point, there is a saving of material and labour no way inconsiderable. The bees, as if acquainted with these principles of solid geometry, follow them most accurately; the bottom of each cell being composed of three planes which make obtuse angles with the side partitions, and with one another, and meet in a point in the middle of the bottom; the three angles of this bottom being supported by three partitions on the other side of the comb, and the point of it by the common intersection of those three partitions.

One instance more of the mathematical skill displayed in the structure of a honeycomb deserves to be mentioned.

It is a curious mathematical problem, at what precise angle the three planes which compose the bottom of a cell ought to meet, in order to make the greatest possible saving, or the least expense, of material and labour.

This is one of those problems, belonging to the higher parts of mathematics, which are called problems of maxima and minima. It has been resolved by some mathematicians, particularly by the ingenious Mr. Maclarurin, by a fluxionary calculation, which is to be found in the transactions of the Royal Society of London. He has determined precisely the angle required; and he found, by the most exact mensuration the subject could admit, that it is the very angle, in which the three planes in the bottom of the cell of a honeycomb do actually meet.

Shall we ask here, who taught the bee the properties of solids, and to resolve problems of maxima and minima? If a honeycomb were a work of human art, every man of common sense, would conclude, without hesitation, that he who invented the construction, must have understood the principles on which it is con

structed.

We need not say that bees know none of these things. They work most geometrically, without any knowledge of geometry; somewhat like a child, who, by turning the handle of an organ, makes good music, without any knowledge of music.

The art is not in the child, but in him who made the organ. In like manner, when a bee makes its combs so geometrically, the geometry is not in the bee, but in that great Geometrician who made the bee, and made all things in number, weight, and measure.

To return to instincts in man; those are most remarkable which appear in infancy, when we are ignorant of every thing necessary to our preservation, and therefore must perish, if we had not an invisible guide, who leads us blindfold in the way we should take, if we had eyes to see it.

Besides the instincts which appear only in infancy, and are intended to supply the want of understanding in that early period, there are many which continue through life, and which supply the defects of our intellectual powers in every period. Of these we may observe three classes.

1st, There are many things necessary to be done for our preservation, which, even when we will to do, we know not the means by which they must be done.

A man knows that he must swallow his food before it can nourish him. But this action requires the cooperation of many nerves and muscles, of which he knows nothing; and if it were to be directed solely by

his understanding and will, he would starve before he learned how to perform it.

Here instinct comes in to his aid. He needs do no more than will to swallow. All the requisite motions of nerves and muscles immediately take place in their proper order, without his knowing or willing any thing about them.

If we ask here, whose will do these nerves and muscles obey? Not his, surely, to whom they belong. He knows neither their names, nor nature, nor office; he never thought of them. They are moved by some impulse, of which the cause is unknown, without any thought, will, or intention on his part, that is, they are moved instinctively.

This is the case, in some degree, in every voluntary motion of our body. Thus, I will to stretch out my arm. The effect immediately follows. But we know that the arm is stretched out by the contraction of certain muscles; and that the muscles are contracted by the influence of the nerves. I know nothing, I think nothing, either of nerves or muscles, when I stretch out my arm; yet this nervous influence and this contraction of the muscles, uncalled by me, immediately produce the effect which I willed. This is, as if a weight were to be raised, which can be raised only by a complication of levers, pullies, and other mechanical powers, that are behind the curtain, and altogether unknown to me. I will to raise the weight; and no sooner is this volition exerted, than the machinery behind the curtain falls to work and raises the weight.

If such a case should happen, we would conclude, that there is some person behind the curtain, who knew my will, and put the machine in motion to execute it.

The case of my willing to stretch out my arm, or to swallow my food, has evidently a great similarity to

this. But who it is that stands behind the curtain, and sets the internal machinery agoing, is hid from us; so strangely and wonderfully are we made. This, however, is evident, that those internal motions are. not willed nor intended by us, and therefore are instinctive.

A second case in which we have need of instinct, even in advanced life, is, when the action must be so frequently repeated, that to intend and will it every time it is done, would occupy too much of our thought, and leave no room for other necessary employments of the mind.

We must breathe often every minute, whether awake or asleep. We must often close the eyelids, in order to preserve the lustre of the eye. If these things required particular attention and volition every time they are done, they would occupy all our thought. Nature therefore gives an impulse to do them as often as is necessary, without any thought at all. They consume no time, they give not the least interruption to any exercise of the mind; because they are done by instinct.

A third case, in which we need the aid of instinct, is, when the action must be done so suddenly, that there is no time to think and determine. When a man loses his balance, either on foot or on horseback, he makes an instantaneous effort to recover it by instinct. The effort would be in vain, if it waited the determination of reason and will.

When any thing threatens our eyes, we wink hard by instinct, and can hardly avoid doing so, even when we know that the stroke is aimed in jest, and that we are perfectly safe from danger. I have seen this tried upon a wager, which a man was to gain if he could keep his eyes open, while another aimed a stroke at them in jest. The difficulty of doing this shows that

there may be a struggle between instinct and will; and that it is not easy to resist the impulse of instinct, even by a strong resolution not to yield to it.

Thus the merciful Author of our nature, has adapted our instincts to the defects, and to the weakness of our understanding. In infancy we are ignorant of every thing; yet many things must be done by us for our preservation: these are done by instinct. When we grow up, there are many motions of our limbs and bodies necessary, which can be performed only by a curious and complex internal machinery; a machinery of which the bulk of mankind are totally ignorant, and which the most skilful anatomist knows but imperfectly. All this machinery is set agoing by instinct. We need only to will the external motion, and all the internal motions, previously necessary, to the effect, take place of themselves, without our will or command.

Some actions must be so often repeated, through the whole of life, that, if they required attention and will, we should be able to do nothing else: these go on regularly by instinct.

Our preservation from danger often requires such sudden exertions, that there is no time to think and to determine accordingly, we make such exertions by instinct.

Another thing in the nature of man, which I take to be partly, though not wholly, instinctive, is his proneness to imitation.

Aristotle observed long ago, that man is an imitative animal. He is so in more respects than one. He is disposed to imitate what he approves. In all arts men learn more, and more agreeably by example than by rules. Imitation by the chissel, by the pencil, by description, prosaic, and poetical, and by action and gesture, have been favourite and elegant entertainments of the whole species. In all these cases, however, the