Buffon asserts, that a hawk or eagle can travel two hundred leagues in ten hours, and relates a story of one that travelled two hundred and fifty leagues in sixteen hours.

A Newfoundland dog has in like manner been brought from Plymouth to London by water, and having got loose, has run home by land with a speed so rapid as to prove that his course must have been nearly in a straight line, though every inch of it was unknown to him.

At such instances we start back, and as far as we can, we disbelieve them, and think we become wise in proportion as we become sceptical. Meanwhile nature pursues her wonder-working course, equally uninfluenced by our doubts or our convictions.*

The fact of the migratory power of one kind of animals confirms the fact of the migratory power of others. While the question was confined to birds it was too often denied by many naturalists, merely from the difficulty of accounting for it and it was said, in opposition to Catesby and White, and all our best ornithologists, that our summer birds only disappear by creeping into holes and crevices to hybernate. And hence, even so late as 1823, the late Dr. Jenner felt himself called upon to examine such assertions with a view of disproving them; which he has done in one of the most agreeable essays on the natural history of migratory birds to be found in our own or any other language. "A little reflection," says he, "must compel us to confess that they are endowed with discriminating powers totally unknown to, and for ever unattainable by, man. I have no objection to admit the possibility that birds may be overtaken by the cold of winter, and thus be thrown into the situation of other animals which remain torpid at that season; though I must own I never witnessed the fact, nor could I ever obtain evidence on the subject that was to me satisfactory; but, as it has been often asserted, may I be allowed to suppose that some deception

Even among mankind, however, we occasionally meet with a sort of sensation altogether as wonderful and inexplicable. For there are some persons so peculiarly affected by the presence of a particular object, that is neither seen, smelt, tasted, heard, or touched, as not only to be conscious of its presence, but to be in an agony till it is removed. The vicinity of a cat not unfrequently produces such an effect; and I have been a witness to the most decisive proofs of this in several instances. It is possible that the anomalous sense may in this instance result from a peculiar irritability in some of the nervous branches of the organ of smell, which may render them capable of being irritated in a new and peculiar manner: but the persons thus affected are no more conscious of an excitement in this organ of sense than in any other; and from the originality of the sensation itself find no terms in any language by which the sensation can be expressed.

Sharks and rays are generally supposed by naturalists to be endowed with a peculiar sense in the organ of a tubular structure found immediately under the integuments of the head, though they

might have been practised with the design of misleading those to whom it might seem to have appeared obvious?" Phil. Trans. 1824, p. 11. The strongest argument against all such disbelief, arising from the difficulty of accounting for the migration of birds, is to turn to the migration of fishes, and to the parallel cases of remote travel in other animals, which are given above. The respective marvels give support to each other, till disbelief itself becomes at length the greatest marvel of the whole.

have not agreed as to the exact character of this additional sense. Trevannius calls it generally a sixth organ of sensation. M. Jacobson, and Dr. de Blainville, who quotes his authority, regard it as a local organ of touch. M. Roux, who seems to have examined it with great attention, believes it to be the source of a feeling of a middle nature between the two senses of touch and hearing.* The bat appears to have, in like manner, an additional sensific power, for it is observed to avoid external objects when in their vicinity, while the eye, ear, and nose are closed, and there is no direct touch and this peculiar feeling has been called a sixth sense generally by naturalists, without discriminating it farther.

What is the cause of those peculiar sensations which we denominate hunger and thirst? A thousand theories have been advanced to account for them, but all have proved equally unsatisfactory, and have died one after another almost as soon as they have received a birth. We trace indeed the organs in which they immediately reside, and know by the sensations themselves that the one exists in the region of the stomach, and the other in that of the throat but though we call them sensations, they have neither of them any of the common characters of touch, taste, hearing, seeing, or smelling.

Foods and drinks are the natural and common means of quieting their pain, but there are other means that may be also employed for this purpose,

*See further on this subject, Edinb. Journ. of Science No. II. Art. I. p. 87. 1825.

and which are often found to answer as a temporary substitute; as, for instance, pressure against the coats of the stomach in the case of hunger, and stimulating the salivary glands in the case of thirst. It is hence that chewing a mouthful of hay alone, or merely moistened with water, proves so refreshing to a tired horse, and is found so serviceable when we dare not allow him to slake his thirst by drinking. Savages and savage beasts are equally sensible of the advantage of pressure in the case of hunger, and resort to it upon all occasions in which they cannot take off the pain in the usual way.

The manis or pangolin tribes, that swallow their food whole, will swallow stones or coals or any other substance, if they cannot obtain nutriment: not that their instinct deceives them, but for the purpose of acquiring such a pressure as may blunt the sense of hunger, which is found so corroding. Almost all carnivorous beasts pursue the same plan; and a mixture of pieces of coal, stone, slate, and earth, is often met with in the stomach of ostriches, cassowaries, and even toads. The Kamschatkadale obtains the same purpose by swallowing saw-dust; and some of the northern Asiatic tribes by a board placed over the region of the stomach, and tightened behind with cords, in proportion to the severity of the suffering. Even in our own country we often pursue the same end by the same means; and employ a tight handkerchief, instead of a tightened stomach-board.

In consequence of this difference in the mode in which the matter of touch or general feeling is secreted under different circumstances, we may also perceive why some parts of the body, although

perhaps as largely furnished with the nerves of touch or general feeling as other parts, are far less sensible and irritable; as the bones, the teeth, and the tendons; and why the very same parts should, under other circumstances, as when morbidly affected, become the most sensible or irritable of all the organs of the system; a fact well known to all, but I believe not hitherto satisfactorily accounted for by any one.

We may see also why inflammation, attacking different organs of the body, should be accompanied with very different sensations. In the bones and cartilages, except in extreme cases, it is accompanied with a dull and heavy pain; in the brain, with an oppressive and stupifying pain; and in the stomach, with a nauseating uneasiness. So, again, in the skin, muscles, and cellular membrane, it is a pain that rouses and excites the system generally; but in those parts which are supplied with the two branches of nerves which are called par vagum and sympathetic, as the loins and kidneys, the patient is affected with lowness of spirits from the first attack of the inflammation. *

Dr. Gall, whose physiological theory has excited so much attention of late years on the Continent, has endeavoured to account for all these varieties of feeling, and, indeed, for all the animal senses of every kind, both external and internal, by supposing some particular part of the brain to be allotted to each, and that the general character and temperament of the individual is the result of the different

* Hunter on Blood, pp. 289, 290.