4. Turkey, partridge, pheasant, fowl, eggs.

5. Pike, perch, gudgeon, trout, grayling.

II. Milk, cream, b.u.t.ter, b.u.t.termilk, whey, cheese.

III. Wheat, barley, oats, peas, potatoes, turnips, carrots, cabbage, asparagus, artichoke, spinach, beet, apple, pear, plum, apricot, nectarine, peach, strawberry, grape, orange, melon, cuc.u.mber, dried figs, raisins, sugar, honey. With a great variety of other roots, seeds, leaves, and fruits.

IV. Water, river-water, spring-water, calcareous earth.

V. Air, oxygene, azote, carbonic acid gas.

VI. Nutritive baths and clysters, transfusion of blood.

VII. Condiments.

ART. II.

INCITANTIA.

I. 1. Those things, which increase the exertions of all the irritative motions, are termed incitantia. As alcohol, or the spirituous part of fermented liquors, opium, and many drugs, which are still esteemed poisons, their proper doses not being ascertained. To these should be added the exhilarating pa.s.sions of the mind, as joy, love: and externally the application of heat, electricity, aether, essential oils, friction, and exercise.

2. These promote both the secretions and absorptions, increase the natural heat, and remove those pains, which originate from the defect of irritative motions, termed nervous pains; and prevent the convulsions consequent to them. When given internally they induce costiveness, and deep coloured urine; and by a greater dose intoxication, and its consequences.

II. OBSERVATIONS ON THE INCITANTIA.

I. 1. Opium and alcohol increase all the secretions and absorptions. The increase of the secretion of sensorial power appears from the violent exertions of drunken people; the secretion of sweat is more certainly excited by opium or wine than by any other medicine; and the increase of general heat, which these drugs produce, is an evidence of their effect in promoting all the secretions; since an increase of secretion is always attended with increase of heat in the part, as in hepatic and other inflammations.

2. But as they at the same time promote absorption; those fluids, which are secreted into receptacles, as the urine, bile, intestinal and pulmonary mucus, have again their thinner parts absorbed; and hence, though the quant.i.ty of secreted fluid was increased, yet as the absorption was also increased, the excretion from these receptacles is lessened; at the same time that it is deeper coloured or of thicker consistence, as the urine, alvine feces, and pulmonary mucus. Whereas the perspiration being secreted on the surface of the body is visible in its increased quant.i.ty, before it can be reabsorbed; whence arises that erroneous opinion, that opium increases the cutaneous secretion, and lessens all the others.

3. It must however be noted, that after evacuations opium seems to promote the absorptions more than the secretions; if you except that of the sensorial power in the brain, which probably suffers no absorption. Hence its efficacy in restraining haemorrhages, after the vessels are emptied, by promoting venous absorption.

4. In ulcers the matter is thickened by the exhibition of opium from the increased absorption of the thinner parts of it; but it is probable, that the whole secretion, including the part which is absorbed, is increased; and hence new fibres are secreted along with the matter, and the ulcer fills with new granulations of flesh. But as no ulcer can heal, till it ceases to discharge; that is, till the absorption becomes as great as the excretion; those medicines, which promote absorption only, are more advantageous for the healing an ulcer after it is filled with new flesh; as the Peruvian bark internally; with bandages and solutions of lead externally.

5. There are many pains which originate from a want of due motion in the part, as those occasioned by cold; and all those pains which are attended with cold extremities, and are generally termed nervous. These are relieved by whatever excites the part into its proper actions, and hence by opium and alcohol; which are the most universal stimulants we are acquainted with. In these cases the effect of opium is produced, as soon as the body becomes generally warm; and a degree of intoxication or sleep follows the cessation of the pain.

These nervous pains (as they are called) frequently return at certain periods of time, and are also frequently succeeded by convulsions; in these cases if opium removes the pain, the convulsions do not come on. For this purpose it is best to exhibit it gradually, as a grain every hour, or half hour, till it intoxicates. Here it must be noted, that a much less quant.i.ty will prevent the periods of these cold pains, than is necessary to relieve them after their access. As a grain and half of opium given an hour before the expected paroxysm will prevent the cold fit of an intermittent fever, but will not soon remove it, when it is already formed. For in the former case the usual or healthy a.s.sociations or catenations of motion favour the effect of the medicine; in the latter case these a.s.sociations or catenations are disordered, or interrupted, and new ones are formed, which so far counteract the effect of the medicine.

When opium has been required in large doses to ease or prevent convulsions, some have advised the patient to omit the use of wine, as a greater quant.i.ty of opium might then be exhibited; and as opium seems to increase absorption more, and secretion less, than vinous spirit; it may in some cases be useful to exchange one for the other; as in diseases attended with too great evacuation, as diarrhoea, and dysentery, opium may be preferable; on the contrary in teta.n.u.s, or locked-jaw, where inflammation of the system might be of service, wine may be preferable to opium; see Cla.s.s III. 1. 1.

13. I have generally observed, that a mixture of spirit of wine and warm water, given alternately with the doses of opium, has soonest and most certainly produced that degree of intoxication, which was necessary to relieve the patient in the epilepsia dolorifica.

6. There is likewise some relief given by opium to inflammatory pains, or those from excess of motion in the affected part; but with this difference, that this relief from the pains, and the sleep, which it occasions, does not occur till some hours after the exhibition of the opium. This requires to be explained; after the stimulus of opium or of alcohol ceases, as after common drunkenness, a consequent torpor comes on; and the whole habit becomes less irritable by the natural stimuli. Hence the head-achs, sickness, and languor, on the next day after intoxication, with cold skin, and general debility. Now in pains from excess of motion, called inflammatory pains, when opium is given, the pain is not relieved, till the debility comes on after the stimulus ceases to act; for then after the greater stimulus of the opium has exhausted much of the sensorial power; the less stimulus, which before caused the pain, does not now excite the part into unnatural action.

In these cases the stimulus of the opium first increases the pain; and it sometimes happens, that so great a torpor follows, as to produce the death or mortification of the affected part; whence the danger of giving opium in inflammatory diseases, especially in inflammation of the bowels; but in general the pain returns with its former violence, when the torpor above mentioned ceases. Hence these pains attended with inflammation are best relieved by copious venesection, other evacuations, and the cla.s.s of medicines called torpentia.

7. These pains from excess of motion are attended with increased heat of the whole, or of the affected part, and a strong quick pulse; the pains from defect of motion are attended with cold extremities, and a weak pulse; which is also generally more frequent than natural, but not always so.

8. Opium and alcohol are the only two drugs, we are much acquainted with, which intoxicate; and by this circ.u.mstance are easily distinguished from the secernentia and sorbentia. Camphor, and cicuta, and nicotiana, are thought to induce a kind of intoxication; and there are many other drugs of this cla.s.s, whose effects are less known, or their doses not ascertained; as atropa belladonna, hyocyamus, stramonium, prunus laurocerasus, menispermum, cynoglossum, some fungi, and the water distilled from black cherry-stones; the last of which was once much in use for the convulsions of children, and was said to have good effect; but is now improvidently left out of our pharmacopias. I have known one leaf of the laurocerasus, shred and made into tea, given every morning for a week with no ill consequence to a weak hysteric lady, but rather perhaps with advantage.

9. The pernicious effects of a continued use of much vinous spirit is daily seen and lamented by physicians; not only early debility, like premature age, but a dreadful catalogue of diseases is induced by this kind of intemperance; as dropsy, gout, leprosy, epilepsy, insanity, as described in Botanic Garden, Part II. Canto III. line 357. The stronger or less diluted the spirit is taken, the sooner it seems to destroy, as in dram-drinkers; but still sooner, when kernels of apricots, or bitter almonds, or laurel-leaf, are infused in the spirit, which is termed ratafia; as then two poisons are swallowed at the same time. And vinegar, as it contains much vinous spirit, is probably a noxious part of our diet. And the distilled vinegar, which is commonly sold in the shops, is truly poisonous, as it is generally distilled by means of a pewter or leaden alembic-head or worm-tube, and abounds with lead; which any one may detect by mixing with it a solution of liver of sulphur. Opium, when taken as a luxury, not as a medicine, is as pernicious as alcohol; as Baron de Tott relates in his account of the opium-eaters in Turkey.

10. It must be observed, that a frequent repet.i.tion of the use of this cla.s.s of medicines so habituates the body to their stimulus, that their dose may gradually be increased to an astonishing quant.i.ty, such as otherwise would instantly destroy life; as is frequently seen in those, who accustom themselves to the daily use of alcohol and opium; and it would seem, that these unfortunate people become diseased as soon as they omit their usual potations; and that the consequent gout, dropsy, palsy, or pimpled face, occur from the debility occasioned from the want of accustomed stimulus, or to some change in the contractile fibres, which requires the continuance or increase of it. Whence the cautions necessary to be observed are mentioned in Sect. XII. 7. 8.

11. It is probable, that some of the articles in the subsequent catalogue do not induce intoxication, though they have been esteemed to do so; as tobacco, hemlock, nux vomica, stavisagria; and on this account should rather belong to other arrangements, as to the secernentia, or sorbentia, or invertentia.

II. 1. Externally the application of heat, as the warm bath, by its stimulus on the skin excites the excretory ducts of the perspirative glands, and the mouths of the lymphatics, which open on its surface, into greater action; and in consequence many other irritative motions, which are a.s.sociated with them. To this increased action is added pleasurable sensation, which adds further activity to the system; and thus many kinds of pain receive relief from this additional atmosphere of heat.

The use of a warm bath of about 96 or 98 degrees of heat, for half an hour once a day for three or four months, I have known of great service to weak people, and is perhaps the least noxious of all unnatural stimuli; which however, like all other great excitement, may be carried to excess, as complained of by the ancients. The unmeaning application of the words relaxation and bracing to warm and cold baths has much prevented the use of this grateful stimulus; and the misuse of the term warm-bath, when applied to baths colder than the body, as to those of Buxton and Matlock, and to artificial baths of less than 90 degrees of heat, which ought to be termed cold ones, has contributed to mislead the unwary in their application.

The stimulus of wine, or spice, or salt, increases the heat of the system by increasing all or some of the secretions; and hence the strength is diminished afterwards by the loss of fluids, as well as by the increased action of the fibres. But the stimulus of the warm-bath supplies heat rather than produces it; and rather fills the system by increased absorption, than empties it by increased secretion; and may hence be employed with advantage in almost all cases of debility with cold extremities, perhaps even in anasarca, and at the approach of death in fevers. In these cases a bath much beneath 98 degrees, as of 80 or 85, might do injury, as being a cold-bath compared with the heat of the body, though such a bath is generally called a warm one.

The activity of the system thus produced by a bath of 98 degrees of heat, or upwards, does not seem to render the patients liable to take cold, when they come out of it; for the system is less inclined to become torpid than before, as the warmth thus acquired by communication, rather than by increased action, continues long without any consequent chillness. Which accords with the observation of Dr. Fordyce, mentioned in Sup. I. 5. 1. who says, that those who are confined some time in an atmosphere of 120 or 130 degrees of heat, do not feel cold or look pale on coming into a temperature of 30 or 40 degrees; which would produce great paleness and sensation of coldness in those, who had been some time confined in an atmosphere of only 86 or 90 degrees of heat. Treatise on Simple Fever, p. 168.

Hence heat, where it can be confined on a torpid part along with moisture, as on a scrophulous tumour, will contribute to produce suppuration or resolution. This is done by applying a warm poultice, which should be frequently repeated; or a plaster of resin, wax, or fat; or by covering the part with oiled silk; both which last prevent the perspirable matter from escaping as well as the heat of the part, as these substances repel moisture, and are bad conductors of heat. Another great use of the stimulus of heat is by applying it to torpid ulcers, which are generally termed scrophulous or s...o...b..tic, and are much easier inclined to heal, when covered with several folds of flannel.

Mr. ---- had for many months been afflicted with an ulcer in perinaeo, which communicated with the urethra, through which a part of his urine was daily evacuated with considerable pain; and was reduced to a great degree of debility. He used a hot-bath of 96 or 98 degrees of heat every day for half an hour during about six months. By this agreeable stimulus repeated thus at uniform times not only the ulcer healed, contrary to the expectation of his friends, but he acquired greater health and strength, than he had for some years previously experienced.

Mrs. ---- was affected with transient pains, which were called nervous spasms, and with great fear of diseases, which she did not labour under, with cold extremities, and general debility. She used a hot-bath every other day of 96 degrees of heat for about four months, and recovered a good state of health, with greater strength and courage, than she had possessed for many months before.

Mr. Z. a gentleman about 65 years of age, who had lived rather intemperately in respect to vinous potation, and had for many years had annual visits of the gout, which now became irregular, and he appeared to be losing his strength, and beginning to feel the effects of age. He used a bath, as hot as was agreeable to his sensations, twice a week for about a year and half, and greatly recovered his health and strength with less frequent and less violent returns of regular gout, and is now near 80 years of age.

When Dr. Franklin, the American philosopher, was in England many years ago, I recommended to him the use of a warm-bath twice a week to prevent the too speedy access of old age, which he then thought that he felt the approach of, and I have been informed, that he continued the use of it till near his death, which was at an advanced age.

All these patients were advised not to keep themselves warmer than their usual habits, after they came out of the bath, whether they went into bed or not; as the design was not to promote perspiration, which weakens all const.i.tutions, and seldom is of service to any. Thus a flannel shirt, particularly if it be worn in warm weather, occasions weakness by stimulating the skin by its points into too great action, and producing heat in consequence; and occasions emaciation by increasing the discharge of perspirable matter; and in both these respects differs from the effect of warm bathing, which communicates heat to the system at the same time that it stimulates it, and causes absorption more than exhalation.

2. The effect of the pa.s.sage of an electric shock through a paralytic limb in causing it to contract, besides the late experiments of Galvani and Volta on frogs, int.i.tle it to be cla.s.sed amongst universal stimulants.

Electric shocks frequently repeated daily for a week or two remove chronical pains, as the pleurodyne chronica, Cla.s.s I. 2. 4. 14. and other chronic pains, which are termed rheumatic, probably by promoting the absorption of some extravasated material. Scrophulous tumours are sometimes absorbed, and sometimes brought to suppurate by pa.s.sing electric shocks through them daily for two or three weeks.

[Ill.u.s.tration]

Miss ----, a young lady about eight years of age, had a swelling about the size of a pigeon's egg on her neck a little below her ear, which long continued in an indolent state. Thirty or forty small electric shocks were pa.s.sed through it once or twice a day for two or three weeks, and it then suppurated and healed without difficulty. For this operation the coated jar of the electric machine had on its top an electrometer, which measured the shocks by the approach of a bra.s.s k.n.o.b, which communicated with the external coating to another, which communicated with the internal one, and their distance was adjusted by a screw. So that the shocks were so small as not to alarm the child, and the acc.u.mulated electricity was frequently discharged, as the wheel continued turning. The tumour was inclosed between two other bra.s.s k.n.o.bs, which were fixed on wires, which pa.s.sed through gla.s.s tubes, the tubes were cemented in two grooves on a board, so that at one end they were nearer each other than at the other, and the k.n.o.bs were pushed out so far as exactly to include the tumour, as described in the annexed plate, which is about half the size of the original apparatus.

Inflammations of the eyes without fever are frequently cured by taking a stream of very small electric sparks from them, or giving the electric sparks to them, once or twice a day for a week or two; that is, the new vessels, which const.i.tute inflammation in these inirritable const.i.tutions, are absorbed by the activity of the absorbents induced by the stimulus of the electric aura. For this operation the easiest method is to fix a pointed wire to a stick of sealing wax, or to an insulating handle of gla.s.s, one end of this wire communicates with the prime conductor, and the point is approached near the inflamed eye in every direction.

III. Externally the application of ether, and of essential oils, as of cloves or cinnamon, seem to possess a general stimulating effect. As they instantly relieve tooth-ach, and hiccough, when these pains are not in violent degree; and camphor in large doses is said to produce intoxication; this effect however I have not been witness to, and have reason to doubt.

The manner in which ether and the essential oil operate on the system when applied externally, is a curious question, as pain is so immediately relieved by them, that they must seem to penetrate by the great fluidity or expansive property of a part of them, as of their odoriferous exhalation or vapour, and that they thus stimulate the torpid part, and not by their being taken up by the absorbent vessels, and carried thither by the long course of circulation; nor is it probable, that these pains are relieved by the sympathy of the torpid membrane with the external skin, which is thus stimulated into action; as it does not succeed, unless it is applied over the pained part. Thus there appears to be three different modes by which extraneous bodies may be introduced into the system, besides that of absorption. 1st. By ethereal transition, as heat and electricity; 2d. by chemical attraction, as oxygen; and 3d. by expansive vapour, as ether and essential oils.

IV. The perpetual necessity of the mixture of oxygen gas with the blood in the lungs evinces, that it must act as a stimulus to the sanguiferous system, as the motions of the heart and arteries presently cease, when animals are immersed in airs which possess no oxygen. It may also subsequently answer another important purpose, as it probably affords the material for the production of the sensorial power; which is supposed to be secreted in the brain or medullary part of the nerves; and that the perpetual demand of this fluid in respiration is occasioned by the sensorial power, which is supposed to be produced from it, being too subtle to be long confined in any part of the system.

Another proof of the stimulant quality of oxygen appears from the increased acrimony, which the matter of a common abscess possesses, after it has been exposed to the air of the atmosphere, but not before; and probably all other contagious matters owe their fever-producing property to having been converted into acids by their union with oxygen.

As oxygen penetrates the fine moist membranes of the air-vessels of the lungs, and unites with the blood by a chemical attraction, as is seen to happen, when blood is drawn into a bason, the lower surface of the cra.s.samentum is of a very dark red so long as it is covered from the air by the upper surface, but becomes florid in a short time on its being exposed to the atmosphere; the manner of its introduction into the system is not probably by animal absorption but by chemical attraction, in which circ.u.mstance it differs from the fluids before mentioned both of heat and electricity, and of ether and essential oils.

As oxygen has the property of pa.s.sing through moist animal membranes, as first discovered by the great Dr. Priestley, it is probable it might be of use in vibices, and petechiae in fevers, and in other bruises; if the skin over those parts was kept moist by warm water, and covered with oxygen gas by means of an inverted gla.s.s, or even by exposing the parts thus moistened to the atmosphere, as the dark coloured extravasated blood might thus become florid, and by its increase of stimulus facilitate its reabsorption.

Two weak patients, to whom I gave oxygen gas in as pure a state as it can easily be procured from Exeter manganese, and in the quant.i.ty of about four gallons a day, seemed to feel refreshed, and stronger, and to look better immediately after respiring it, and gained strength in a short time. Two others, one of whom laboured under confirmed hydrothorax, and the other under a permanent and uniform difficulty of respiration, were not refreshed, or in any way served by the use of oxygen in the above quant.i.ty of four gallons a day for a fortnight, which I ascribed to the inirritability of the diseased lungs. For other cases the reader is referred to the publications of Dr. Beddoes; Confederations on the Use of Fact.i.tious Airs, sold by Johnson, London.