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Our author then proceeds to the very remarkable phenomenon of migration. We are somewhat surprized, considering the time which has now elapsed since Dr. Jenner's researches on this subject have been made public, and the very decisive character of his conclusions, that our author should not only not allude to them, but even continue in the obscure, inconsistent and unfounded opinion which previously prevailed. We shall not here advert any further to this curious topic; but for a full display of this and many other equally wonderful instincts in birds, refer our readers to the late Dr. Jenner's paper in the Philos. Trans. 1824. Part I. (See B. C. September 1824.)
Thus far we may safely apply to the case of birds, the same doctrine which we before applied to that of lower animals, viz.; that the course of actions which they pursue in obedience to what we call instinct, are not the result of a comparison of distinct ideas, however few or simple; but of a sort of conviction arrived at directly without any intermediate steps. The power of apprehension from which this practical result springs, is open only to the perception of those particular objects which are connected with the well-being and wants of the animal; and the number of such objects is extremely limited beyond those limits, though hundreds of other objects affect the external senses, yet none excite that peculiar faculty by which the bird arrives instantaneously at practical conclusions.
But here we come to a new class of facts; to apparent deviations from the ordinary routine of instinct; to certain instances in which upon a particular emergency, the animal has adopted a particular and appropriate resource.
One of the most remarkable ordinary instincts of crows, is observable in the way they contrive to get at oysters and other shell fish. viz; by carrying them to a great height in the air, and then dropping them upon the stones, so as to break the shell. This, however curious, being a regular habit, comes under the class of instinct already spoken of. But what shall we say to the following application of the same method, for a purpose quite different:
"In the spring of 1791, a pair of crows made their nest on a trees in a gentleman's garden; and in his morning walks he had frequently been amused by witnessing furious combats between them and a cat. One morning the battle raged more fiercely than usual, till at last the cat gave way, and took shelter under a hedge, as if to wait a more favourable opportunity of retreating to the house. The crows continued for a short time to make a threatening noise but perceiving that on the ground they could do nothing more than
threaten, one of them lifted a stone from the middle of the garden, and perched with it on a tree planted in the hedge, where she sat watching the motions of the enemy of her young. As the cat crept álong under the hedge, the crow accompanied her by flying from branch to branch, and from tree to tree; and when at last puss ventured to quit her hiding place, the crow leaving the trees, and hovering over her in the air, let the stone drop from on high on her back." P. 81.
Another instance of the same description, is as follows:
"Linnæus informs us, that the martin dwells on the outside of houses in Europe under the eaves; and that when it has built its nest, the sparrow frequently takes possession of it. The martin, unable to dislodge his intruding enemy, convokes his companions, some of whom guard the captive, whilst others bring clay, completely close up the entrance of the nest, then fly away, leaving the sparrow to be suffocated." P. 79.
We shall not detail the account of the mocking bird, nor give the story quoted from Locke, of the Brazilian parrot, who is said to have given rational answers to some questions put by a person who had never before seen him. This person, however, did not understand the language in which the bird spoke, and not only might there be a collusion between the interpreters employed, but the same answers might have been returned, for any thing that appears to the contrary, to a very different set of questions.
We shall reserve our remarks upon these extraordinary applications of instinct, till we have briefly traced its powers in the class of quadrupeds.
Of the ordinary instinct displayed by quadrupeds, there are so many instances familiar to our daily observation, that it is unnecessary here to quote any of them, except perhaps one or two, which are too singular to be passed over, and which bear upon the comparison between ordinary and extraordinary instinct.
We cannot fail to observe in general both the higher degree of ordinary instinct, as well as the greater variety of objects to which it is directed in this class of animals, in proportion to their less irritability, their more perfect nervous sensibility, and the greater number and complication of their organs. The beautiful adaptation of habit and disposition to structure, is well illustrated by Dr. H. in the instances of the elephant, the lion, the sloth, and the mole. We observe an undeviating instinct in animals while in their natural state; we find also the effects of difference of situation, and particularly human intercourse, in materially altering their instinctive habits; and beyond this, we find them, in extra
ordinary emergencies, deviating still more from their regular course. In proportion, however, as the ordinary instinct is of a higher kind, those occasional deviations appear less extraordinary, and more approaching the natural order. Bu whatever such alterations may take place, there is never a total change; there is always a similarity preserved to the original character. It is not the loss of one sort of instinct, and the substitution of another, but always a modification of that already possessed. These points of resemblance are highly curious and deserving attention. To observe, collect, classify and combine these points of resemblance and difference, is the only inductive path by which we can pursue our enquiries respecting instinct. We think, therefore, that Dr. Hancock would have been much better employed in making such deductions from the accumulation of facts, than in occupying two-thirds of his book, as he has done, in metaphysical and theological reveries, about the internal illumination of man.
Many instances are adduced to shew the exquisite and almost inconceivable perfection in which some animals enjoy particular senses. This the author is very careful to distinguish from the power of instinct. But there are extraordinary instances of particular actions in animals which seem hardly capable of being referred to an extraordinary perfection in any of the known senses, however exquisite. For example, the power by which animals will find their way from an incredible distance through an unknown country to their home. Instances are familiar in the dog and the horse; similar stories are here related of the ass and the sheep. Some persons have attributed this power to a sixth sense; which has also been the case in regard to some instances related of human beings, who have, in some manner not accounted for, been able to feel the presence of certain objects not perceptible to any of the ordinary senses. Whatever may be the real cause, it is clearly a case in which reasoning is not concerned.
Considering these instances either as referable to some hidden physical influence, or as at least belonging to natural instinct, we have to observe in general, that its ordinary display is always found in exact proportion to the perfection of the animal's organization, as well as confined to those particular objects which are connected with its well-being: never directed to the attainment of any end beyond these, and never exercised by any other means than those which are afforded by the peculiar organization of the animal, and the habits. which are naturally characteristic of its kind.
VOL. XXIII. JANUARY, 1825.
With respect to the effects of human intercourse on the lower animals, we may cite the case of oxen. These, when wild, possess a spirit and fierceness which render them extremely formidable. They possess, also, such acuteness of smell as to trace the footsteps of men over the grass, at which they always display peculiar symptoms of rage and horror. However different this is from the domestic state of cattle, it is still more so from the state to which they are brought in some countries by education. Among the Hottentots they are trained to a variety of useful domestic labours; and not only this, but are made use of in war: at a signal they fall upon the enemy, striking with their horns and hoofs, overturn and trample upon whatever resists them, and thus completely break the ranks, and pave the way for an easy victory to their masters. They are also instructed to guard the flocks, and defend them from beasts of prey, and from robbers, whom they distinguish from the keepers, or other persons.
Now, from this instance, we may take occasion to ob serve, that the effect of intercourse with man, and education, does not take away the natural instinct, and substitute an acquired one, but only modifies and extends the powers already possessed by the animals. They still make use of those powers alone which constitute the distinguished feature in their character in all conditions.
Many other instances of this kind are recorded in the work before us; but we must now proceed to the last and highest manifestation of instinct, if so it can be called, in sudden emergencies, and on extraordinary occasions, where something much more like a power of reasoning is displayed. Of this, we have mentioned some instances in birds; those related of quadrupeds are yet more astonishing. In dogs, we have many examples of extraordinary sagacity, in per ceiving the approach of danger to their masters, such as the concealment of a robber or assassin, a leak on board a vessel, and other like occurrences; but in such cases there is always room to suppose their superior power of smell, or other senses, may have guided them. In other cases the power of habit is clearly discernible. In others again, a dog feeling for his master in danger, would naturally so express it, as to communicate the intelligence to others, and thus be the means of saving him. All these cases, though extremely interesting, do not positively require the supposition, that the animal put together distinct ideas, and acted upon the conclusion. Of the astonishing intelligence of the elephant, several instances are mentioned; his management in pushing a carriage up hill, his amazing docility, his recollection of
persons and places from favours bestowed, and his care of children, are truly wonderful, but may be explained by a sort of indefinite feeling, without distinct reasoning. A wellknown anecdote is introduced from Pliny, of a number of these animals, who, when they found themselves condemned to death in the sanguinary games of the circus, by their gestures and cries seemed to implore the compassion of the spectators to a degree which was quite effectual.
To pass over many other instances, which do not appear to us to prove any thing with respect to a reasoning power in animals, we will cite two, which are, perhaps, the strongest on record, and seem to be regarded by our author as decisive proofs.
"Two goats, grazing about the ramparts of Plymouth citadel, got down upon the narrow ledge of the rock, and one of them advancing before the other till it came to an angle was enabled to return: but in its way back, met its companion, which produced a most perplexing dilemma, as it was impossible for them to get past each other. Many persons saw them, without being able to lend any assistance. After a considerable time, one of the goats was observed to kneel down with great caution, and crouch as close as it could lie; which was no sooner done, than the other, with great dexterity, walked over him, and they both returned the way they came in perfect safety. And at Ardinglass, near Glenarm, in Ireland, two goats, moving towards each other over a precipice 1,000 feet high, on a narrow ledge of the rock, were seen to extricate themselves from danger by a similar expedient. In both these instances the animals looked at each other for some time, as if they were considering their situation, and deliberating what was best to be done in the emergency. I apprehend that mere instinct would have prompted them immediately to act, instead of thus comparing and judging by their outward senses of danger and expedients." P. 80.
The other case, which we must quote, is this:
"A lady had a tame bird, which she used to let out of its cage every day. One morning, as it was picking up crumbs from the carpet, her cat, who had always before shewn great kindness to the bird, seized it on a sudden, and jumped with it in her mouth upon a table. The lady, alarmed for the fate of her favourite, on turning about, observed that a strange cat had just come into the room. After turning it out, her own cat came down from her place of safety, and dropped the bird, without inflicting the least injury. Now, it seems very clear, on considering this act, that various circumstances must have influenced this sagacious animal. She must have known that the bird was in danger from this intruder, and must have reflected on the best means of rescue: and we may take it for granted, that instinct could not, on the same principle, have prompted the one cat to destroy, and the other cat to save, at the same moment of time; but the manner in which the preservation was effected