reasoned on their wants: they wished: and it was done. The boa: which originally differed little from the other beasts of the forest, first obtained tusks, because he conceived them to be useful weapons, and then, by another process of reasoning, a thick shield-like shoulder, to defend himself from the tusks of his fellows. The stag, in like manner, formed to himself horns, at once sharp, and branched, for the different purposes of offence, and defence. Some animals obtained wings, others fins, and others swiftness of foot; while the vegetables exerted themselves, in inventing various modes of concealing, and defending their seeds, and honey. These are a few of many instances, adduced by Dr. Darwin, which are all objectionable, on his own principles; as they require us to believe the various propensities, to have been the cause, rather than the effect, of the difference of configuration. The fish did not become a subnatant animal, by having received fins; as it must have been an inhabitant of the water, before it could have felt the want of them: and the hog must originally have had propensities, different from those of the sheep, or it would not have wished, nor attempted, the formation of its snout.

Of all modes of reasoning, that is the easiest, which contents itself, with simple supposition; but to this species of argument no bounds can be fixed. It will prove, as readily, that a single filament gave rise to the complicated system of the universe, as that it gave rise to all the tribes of animals, and vegetables, that inhabit our earth.

If we admit the supposed capacity of producing organs, by the mere feeling of a want, man must have greatly degenerated, or been originally inferior, in power. He may wish for wings, as the other bipeds are supposed to have done with success: but a century of wishes will not render him abler to take flight. It is not, however; to man, that the observation must be confined. No improvements of form have been observed, in the other animals, since the first dawnings of zoology; and we must, therefore, believe them, to have lost the power of production, rather than to have attained all the objects of their desire. If we may be allowed to judge, from their situation, the hare has still, in the chase, the same reason, as the birds of old, to wish for wings, and the dove for greater swiftness of flight, to escape from the pursuing hawk: yet the scale of inferiority still subsists; and such is the order of nature, that the strength of all is supported by the weakness of all.'

On the much-disputed subject of Insanity, Mr. B. has advanced his own hypothesis: he supposes it to depend on peculiarly vivid ideas of imagination. Whether it be strictly philosophical to assume a term merely relative, and applicable to a sound state of mind in many cases, as an exclusive cause of disease, we shall not determine :-but we apprehend, that the various forms of insanity cannot be referred to this, nor to any single cause. Mr. Brown, indeed, has comprehended, under the general term Madness, both the acute and chronic

states

states of the disease, both mania and melancholy. We should doubt whether he has been accustomed to observe the unhappy subjects of these disorders; if he had, it would have been impossible for him, acute as he is, to have confounded the distempers. The maniac often expresses contempt, or hatred, for those to whom he was most warmly attached during health: but, from a more vivid state of his ideas, we should have expected only an extravagant increase, not a change of affection. The author seems, indeed, to have felt the insufficiency of this cause, for he admits that patients combine imagination with their perceptions' in maniacal cases. This expression, though certainly confused and obscure, is worth remarking; because it leads us back to the common doctrine, which constitutes depraved perception as the basis of madness. When the insane person,' says Mr. B. fancies himself a sovereign, he connects ideas of grandeur with every object around him. All is gold, or marble, or purple, or fine linen. His seat is a throne; his chamber, a palace; his keepers, regal guards.' In this case, it is evident that something more than the connection of incongruous ideas is required to explain the phænomenon. There must be a mistake respecting familiar objects; that is, a vitiation of perceptions, in order to give the maniac the impression of gold from an handful of straw, or of purple and fine linen from his blanket. Besides, we know from the accounts of persons who have recovered from maniacal paroxysms, that their perceptions have been much perverted: for patients sometimes recollect, with great accuracy, whatever has impressed their minds during the furious state of insanity. They report that objects have presented a fiery appearance to them; and that their friends have seemed to have assumed figures which excited their horror or disgust.- Mr. Brown is also inaccurate in stating that maniacs are best restrained by terror. This antient doctrine has been happily superseded by the mild and benevolent discipline introduced by Dr. Hunter, in the Asylum of York, and now generally imitated in similar places of confinement.

The opinion of our author applies, however, though with some limitation, to the chronic state of insanity for, in melancholic persons, one or more ideas are felt so acutely, that they divert the mind from its usual operations on others. Yet, in these cases, there is only a partial vivacity of ideas; general impressions become indifferent; and it is sometimes impos-. sible to attract the attention of the patient to the most obvious contradiction of his mistaken opinion. Instead of agreeing with Mr. Brown, therefore, that madness is a disease of the motives alone,' we would say that mania is a disease of perception, and that melancholy is a disease of motives.

It may be observed, as a farther objection to Mr. B.'s theory's that paroxysms of furious insanity often occur after hard drinking, and total want of sleep, for several days and nights suc cessively; that is, when, in the language of Mr. B. the excitability of the brain has been exhausted by the most powerful means. It is impossible, according to his principles, that a vivid state of ideas should be produced by such causes; yet the fact frequently presents itself to medical practitioners.

Respecting the theory of Fever, we agree with the author in thinking that nothing really satisfactory has yet been advanced. If, indeed, we examine some of the most celebrated opinions concerning the proximate cause of fever, we shall find that they all describe nearly the same fact, in different terms. Boerhaave supposed it to consist in obstruction, from the state of the fluids, to the circulation through the extreme or capillary vessels; Hoffman ascribed it to a spasmodic stricture of those vessels; and Dr. Darwin to a torpor of the heart, arteries, and capillaries. All these theories, however different in appearance, enunciate little more than this fact that, during the cold, fit of fever, there is a suspension of circulation in the extreme or capillary vessels. To account for this state of the vessels, is the great desideratum of pathology; and we have to lament that ingenuity has hitherto been baffled in attempting to supply it. The accumulation of sensorial power, which Dr. Darwin supposes to take place during this state, is shewn by Mr. Brown to be inconsistent with his previous hypothesis of the nature of that supposed fluid.

The accumulation, which occasions the increased action, takes place, during the cold fit; and the cold fit is said to be induced, in two modes, by the diminution of stimulus, or by the diminution of sensorial power. Let us consider the possibility of accumualtion, in each of these states.

In the former, a stimulus, of less force, is applied to the natural quantity of sensorial power; and no accumulation can take place, unless it act on a less quantity, than the usual stimulus. If it act on a less quantity, it is evident, that the sensorial power might be diminished, without a diminution of effect, in direct opposition to the laws of animal exertion. Even if it were not in opposition to laws, previously inferred, it would be difficult, to conceive, in what manner, a portion of sensorial power, which would have been expended by a more powerful stimulus, remains unaffected, when a gentler is applied. The whole is affected, in a certain manner; and the whole, or none, must, therefore, be expended.

When the usual stimulus acts on diminished sensorial power, it is evident, that no accumulation can take place, if the supply from the brain continue to be expended, in the same manner, as during the sound state of the organ; and this expenditure must continue,

unless

unless the stimulus have lost its power, or the spirit of animation its excitability.

Even if we suppose the quantity of sensorial power, expended, to be always proportional to the force of the stimulus, without relation to the strength of the organ, accumulation will, indeed, be possible, but the hot fit of fever cannot be induced: for the usual stimulus, whatever be the state of plenitude of the organ, will excite its precise quantity of sensorial power; and thus the motion of the capillaries, and heart, and arteries, will not be increased.'

The author considers the class of Sensitive Fever, also, as irreconcileable with the principles of the Zoonomia: but, having already occupied so large a portion of our Review with extracts from this work, we cannot admit farther quotations.

To conclude, we think that this book is a very respectable specimen of the author's talents and attainments. With much vigour and acuteness of mind, it exhibits a liberal and truly philosophical spirit; and though we have ventured, in some instances, to express a difference of opinion with Mr. Brown, we cannot take leave of his performance without intimating our hope that we shall have fresh occasions, hereafter, of giving our unbiassed suffrage to his abilities.

ART. IV. Essay on the Causes, early Signs, and Prevention of Pulmonary Consumption; for the Use of Parents and Preceptors. By Thomas Beddoes, M. D. 8vo. pp. 274. 5s. Boards. Longman and Rees. 1799.

s this essay is intended for popular instruction, the author professedly avoids several points of discussion, which would have attracted his notice in a book addressed to the faculty. His aim is to engage those, who have the care of chil dren, to guard against the remote causes of pulmonary consumption, and to make them acquainted with the symptoms which characterize the early stage of the disease. The design is benevolent and useful: but how often are medical men themselves deceived, in attempting to discriminate phthisis from other affections, on its first insidious attacks?

Dr. Beddoes thus controverts the opinion entertained by many persons, that there is little suffering in consumption:

The short teazing cough at first, provoked by incessant tickling in the throat, as if the minute fragment of some extraneous body had immoveably fixed itself there; the subsequent hard rending cough, attended sometimes by retching and vomiting, sometimes by stitches which necessitate the most violent struggle against the continued solicitation to cough, and severely punish a moment of inattention; the expectoration sometimes nauseous, always offensive to the eye, and harrassing when it is not free; the languor with which the paREV. JULY, 1799.

U

tient

tient finds himself overpowered, when his attention is not occupied by some among his various fixed or flying pains; the extremes of cold and heat through which he is carried by the daily returns of hectic; the sweats in which his repose by night drenches him; the breathlessness on motion or without motion, arising by degrees to a sense of drowning, and terminating in actual drowning, when there is no longer strength to bring up the fluids secreted in the chest ; the disorder in the bowels, towards the last always threatening, and finally unrestrainable, while it cuts off those indulgencies which the very thirst it creates or aggravates impatiently demands;-these are but a part of the torments under which the physician, during his transient visit, in an immense majority of instances, sees the consumptive labouring. And what are the few minutes of a physician's call, compared to the whole twenty-four hours, lengthened out as they often are to the tenants of the sick chamber, by pain and incapability of amusement on one side, and by tender concern on the other?"

On the subject of climate, as tending to produce phthisis, we meet with many curious and important observations. Dr. Beddoes had conceived, from information, that this disease is little known in the West Indies, but that the Creole women must be liable to it when they come to England. His opinion is confirmed in a letter from Mr. Bryan Edwards, the ingenious historian of the West Indies. In Portugal, Dr. B. tells us, consumptions are frequent; and at Lisbon, it is a common expedient to send patients to the other side of the Tagus.' In Italy, phthisis is very common; and the Island of Madeira does not appear, from our author's facts, to be an eligible residence for consumptive patients.

Our curiosity was much excited by the subject of one of Dr. Beddoes's divisions; the Classes Exempt from consumption. We feel some doubt whether his facts be conclusive in establishing these privileged orders, but the hints are highly deserving of attention; not only with reference to the subject of phthisis, but as they shew the advantage which might result from a complete history of the diseases concomitant on particular arts and professions.

In a letter from Dr. Withering written in 1793, which he allowed me to publish, it is remarked that "the only classes of men he had yet observed exempt from the disease (consumption), are butchers and makers of catgut. They both pass much of their time amidst the stench of dead animal matters, the latter very much so; the former live chiefly on animal food,' and are much exposed to the inclemencies of the seasons, whilst the latter live as other manufacturers, and work under cover in close and rather warm buildings. These persons are always sleek, often fat, and the rosy bloom of health adorns their cheeks." (Letters from Dr. Withering, and others, Dr. Beddoes. Johnson, 1793.)

• Concerning