the full strength of a man, it is impossible to overstock it, like the weaving, with an influx of boys and children.

Although many other manufactures are carried to a great extent in the west of Scotland, both for home consumption and export, all of which must have been partially, and at times severely depressed, none have exhibited vicissitudes, either in market prices or in wages, in any respect comparable with those experienced by the cotton trade. Amongst these may be enumerated the respective manufactures of iron and brass founding, of leather, shoes, boots, gloves, and saddlery, of glass and earthen ware, of soap and candles, brushes, and many other articles, necessary where a great population exists, and which have been considerably extended by a constant exportation, though to an extent always fluctuating. These manufactures have rather kept pace with, than preceded the actual demand; and hence their depression has been seldom particularly remarkable either for severity or continuance.

The mechanical professions, specially employed to supply the home market, have also kept a tolerably steady course, as those of the smith, carpenter, turner, mason, bricklayer, slater, plasterer, &c. The extension both of machinery and building has continued unabated, notwithstanding every depression; and, even in the present year, immense piles of buildings, nay whole streets, are going on with the usual activity. This seems to warrant the conclusion, that suspension of demand, in most trades, is still more severely felt than actual absence of funds; and that capital is to be readily found wherever it is invited by a prospect of profitable in

vestment.

The state of the great manufactures is intimately blended with, and affect ed by, that of external commerce; they act reciprocally upon each other, and generally flourish or suffer together. When manufactures are greatly overstocked at home, foreign markets are always glutted in a short time, either by the speculations of merchants, or by the consignments of manufacturers themselves.

The following proportional table may afford a pretty fair view of the relative extent of the export trade for

The present year not being complete, the ratio is assumed from a view of the first six months. In general, it will be observed that this table rises and falls nearly at the same dates as the former. The chief difference is in 1815. In this year the exports were very extensive; but the prices of cotton weaving were not raised. It had plainly tended, however, to keep them up; for, when the exportation declined in 1816, they instantly fell above 20 per cent., and have continued to decline with the exports, until the present month, when they have revived a little.

Upon the prospects of revival a few remarks may be hazarded. They depend, however, upon contingencies so various, and so widely extended, that we can reach little beyond mere conjecture. The reasons being explicitly stated, every reader will be enabled to judge for himself how far the conclusions are warranted by the premises.

It seems proper to divest the question of all political considerations of ambition or jealousy in any European state, such as might lead, at an early period, to the revival of hostilities, and to view the question solely as connected with a peace establishment, although probably not with a totally unrestricted commercial intercourse. In this situation, the policy of each state will naturally suggest the promotion and extension of its own trade, whether the means shall be judiciously or injudiciously selected.

It seems morally impossible to believe that the cotton weaving branch can maintain its extended state long,

under the existing depression of wages. Either the demand must be increased, or the supply will certainly, though perhaps gradually, diminish, until the rate of labour shall resume nearly its natural level, and place the weaver upon an equality with other artisans. But many obstacles present themselves to the fulfilment of this prospect. In many parts of the Continent, lower money wages will procure an equal or a greater supply of necessaries or comforts. Hence the British wages must be influenced by the competition. Nor has mechanical improvement in the weaving branch so far distanced foreign competitors as to counteract a great difference of prices.

In spinning the case is different; although it is now fully ascertained that not only very extensive, but well regulated, cotton-mills do exist at Rouen and other parts of France. Some of the most extensive spinners in Scotland have actually visited and examined these works, and admit the fact. Still, however, the great capital already vested in spinning establishments in Britain, the matured superiority of machinery,-practical dexterity acquired by long habit, and the minute division of labour, and, above all, the security of property, must continue, for a long time, to operate powerfully in favour of the British spinner.

The exportation of cotton-yarn to the Continent is a great and extending trade. The probability, therefore, is, that Britain will be much more rapidly rivalled in her weaving than in her spinning manufacture, and may export large quantities of her yarn long after she shall cease to experience any considerable demand for her cloths, unless important improvements in weaving machinery shall create a new superiority, as Sir Richard Arkwright's inventions opened an entirely new trade at the conclusion of the American contest.

Upon the whole, it may probably be assumed with truth, that both the commerce and manufactures of Glasgow wear an aspect somewhat more promising than they have exhibited for some years past; but it would certainly be too sanguine to predict a speedy restoration of all the vigour which they have possessed in former times.

Glasgow, Sept. 1817.

D.

ACCOUNT OF DR GOSSE'S METHOD OP PRESERVING THE HEALTH OF MANUFACTURERS AND OTHERS FROM THE BAD EFFECTS OF THE INHALATION OF DUST AND HURTFUL VAPOURS, BY MEANS OF A SPONGE MASK.

THE preservation of the health of our manufacturers and artisans is an object of the highest importance, not only to those immediately interested, but also to the community at large, who participate in all the advantages resulting from the successful exertion of their industry. The inhalation of noxious substances is one of the causes of disease the most difficult to guard against, because respiration cannot be suspended even for a few minutes without danger, and never without inconvenience. The noxious substances which are capable of operating on the body through the medium of the air we breathe, sometimes act merely by mechanical irritation, such as all kinds of fine dust and fibres suspended in the air and carried along with it into the lungs, but more commonly they exist in a state of solution or intimate combination, and act as poisons by their inherent deleterious properties.

Various means have been imagined to preserve workmen whose occupations oblige them to work in contaminated air. In some cases they have been supplied for respiration, by means of tubes, with a purer air brought from some distance. But, from the very nature of the apparatus required for this purpose, it is of very limited application, both on account of its expence, and its being altogether incompatible with the free exertions of the workmen.

Masks of different kinds worn over the face are exposed to inconveniences of another description. A piece of dry linen, for example, applied over the mouth, may serve to exclude, in a great measure, dust and other powders mechanically suspended in the air, but has no effect in correcting the poisonous properties of the deleterious gases. Moist linen is certainly preferable; but it oppresses the breathing when closely applied, and admits the noxious gases when it does not fit exactly, and, besides, it corrects the qualities but of few of them, and that in a slight degree only.

Dr Macquart first proposed, in the article Medicine in the French Encyclopédie, to counteract animal emanations, by filling the nostrils with small sponges imbibed with some aromatic liquor; but this method leaves the mouth undefended.

M. Brizé Fradin invented an apparatus, with the same object in view, and published an account of it, with a plate and description, in a French periodical work, (Annales des Arts et Manufactures. Paris, 1811. Vol. L. p. 203.) Its principle consists in making the air to be inhaled by the mouth pass through a layer of cotton moistened with the liquor best calculated to destroy its hurtful properties. It is, however, too complicated, and somewhat inconvenient in its use; and it only guards the mouth, and leaves the access by the nostrils free. Besides, cotton, by being moistened, loses its elasticity, gathers into a mass, and does not allow the air to pass through it without great difficulty; and, if not sufficiently wetted, is permeable to the emanations intended to be corrected.

These inconveniences induced Dr Gosse of Geneva to resume some experiments on the employment of sponges begun by his father in 1785, and applied by him to the manufacture of hats. The success of these experiments was so great, as to render them deserving of being generally known, with the hope that they may attract the notice of those manufacturers whose workmen suffer from impure emanations, and may thus be the means of prolonging the lives of many useful and industrious citizens.

Dr Gosse's method consists in the application of a mask of fine sponge. It should be selected as much as possible of the shape of a hollow cone, and should be sufficiently large to cover the greater part of the nose, all the mouth, and even the chin. It should apply closely by its margin to the cheeks and chin, while the mouth and point of the nose lie in the hollow of the cone, and, if it be not naturally hollow enough to leave the lips free, it must be kept from them by cross slips of whalebone. When sponges of sufficient size and fineness cannot be got of the required shape, the mask may be made of several pieces joined together; and even a sponge of inferior quality may be covered on the

outside with fine sponge. When properly fitted, it is to be moistened in water or other fluid proper for correcting the poisonous quality of the emanations, and tied over the mouth and nose, so that no air can be received into the lungs but what passes through its pores.

This contrivance is free from almost all the objections to which the others are liable. From the porous and elastic nature of sponge, it is easily made to apply closely round the edges, while it permits the air to permeate it freely, and thus does not impede either respiration or speech. It is less inconvenient when used even for a length of time, than could be imagined, and does not at all interfere with the motions of the head or the exertions of the workman. It is not costly, and is easily kept clean. Still its use is sometimes exposed to objections. It keeps the inspired air always moist, which Dr Gosse thinks might be prejudicial to persons disposed to catarrhal affections; and the fluid with which it is necessary sometimes to moisten it, discolours the skin. Also in violent exertion, causing repeated and deep inspirations, it may excite a transient difficulty of breathing. But these inconveniences, trifling in themselves, compared with the evils which it is capable of counteracting, become almost entirely removed by practice, and may in a great measure be avoided by taking care not to use the solutions with which the sponge is moistened, in too concentrated a state, and in removing it from time to time to breath the fresh air, and to wash the face with cold water.

The sponge mask merely soaked with water is sufficient to guard the wearer against the effect of any powder whatever, and is therefore applicable to the grinders of colours, drugs, and stucco, stone-cutters, cotton-spinners, feather-cleaners, wool-carders, hatmakers, &c. &c.

Water will also serve the purpose of condensing mercurial vapours, and the more easily that the rapid evaporation which takes place lowers the temperature. For the same reason, the wet sponge mask enables the face to support the heat of an intense fire, to which some professions are exposed, gilders upon metal, lookingglass manufacturers, goldsmiths, baro

meter-makers, glass-blowers, assayers, metal-casters, enamellers, &c. &c.

For water we may substitute a solution of salt of tartar, in the proportion of one ounce of the salt to eight of water, to neutralize most of the acid vapours or gases which affect the manufacturers of nitrous acid, aqua fortis, muriatic and oxymuriatic acid, bleachers, chemists, engravers, &c. &c. Water acidulated with vinegar, a mineral acid, or even oxymuriatic acid, may be used to counteract the miasma to which physicians are exposed in visiting infected places, anatomists in performing juridical dissections, and gravediggers, or those employed to bury the dead in times of pestilence.

A solution of sugar of lead in the proportion of one ounce and a half to two pints of rain water, may be used when the workman is exposed to sulphureous or ammoniacal vapours, as they are speedily decomposed by the saturnine solution. Accidents from this cause are not very common in this country, but several men perished at Leadhills from inhaling sulphuretted hydrogen gas on the 1st March 1817. In Paris, however, it is a very frequent cause of accidents to the men employed in emptying the soilpits.

The exposure to carbonic acid gas for a short time may be rendered less dangerous by wearing the mask soaked in lime-water.

Many vapours have a local effect on the eyes, which is the more troublesome, that the light then becomes a new source of irritation. It is, therefore, not wonderful to see in some manufactories incurable ophthalmias, weakness of sight, and blindness, a frequent consequence. The means hitherto employed to prevent these, far from being of use, rather aggravate the evil, and incommode the vision. It is impossible to make spectacleframes to fit closely around the eye, and if they be guarded with any kind of cloth, the heat of the confined air becomes insupportable, and the glasses soon grow dim. The sponge furnishes us with a valuable means of obviating these inconveniences. By cutting oval rings of it, it serves for the frame, upon the fore part of which the glasses are to be fixed by pitch, or some other cement, insoluble in water, and by means of ribbons tied around the

head, they are easily fitted quite tight around the orbits. Water will serve in most cases to wet these sponge frames, but sometimes it may be slightly acidulated or alkalized. Sponge moistened spectacles would, therefore, be of great service to nightmen employed in cleaning soil-pits, manufacturers of acid, and in general all workmen exposed to irritating vapours and great heat.

The real advantages to be obtained from the methods here proposed, can only be ascertained by long experience; but the following experiments made by Dr Gosse prove, that they are entitlel to some confidence, and deserve the attention of those to whose professions they are adapted.

With a sponge mask soaked in water, Dr Gosse stood beside the workman in a hatmaker's while engaged in the process of bowing the hair. The dust, which is very irritating, and contains dried blood and nitrate of mercury, rose in such quantity, that a person could scarcely be distinguished at eight paces distance. The workman, although exposed to a current of air, coughed a great deal, could not speak, and suffered from a headach, which obliged him to interrupt his occupation from time to time. In fact, the bowers are subject to various nervous and pulmonary disorders, and all die young. But Dr Gosse remained two hours in this place without any inconvenience; wishing, however, to take off the mask for a little, he was seized with catarrh and sore throat, which lasted till next day. The outside of the mask got covered with a thick coating of dust and hair, which was easily removed. This experiment was often repeated in workshops where the air was loaded with injurious dust, and always with the same results.

Dr Gosse also exposed himself, guarded by the wet sponge, to the vapour of mercury, raised by heating four ounces in a crucible. To ascertain whether the mercury penetrated the mask, he lined it with goldleaf. In ten minutes an ounce and a half of mercury were evaporated. Dr Gosse's hair and the sponge were covered with a grey powder, which, on being washed, collected into metallic globules. His respiration was not affected, and the gold was not tarnished, except in one spot exposed by

mistake. The experiment was repeated with perfect success.

The sponge mask and sponge mounted spectacles also succeeded in preventing any bad effects from the vapour of burning sulphur. Six ounces of bruised sulphur were thrown upon a brazier in a close apartment. The fumes were very abundant, and nobody could enter the room without the risk of being suffocated. But guarded by the sponge, wet with a solution of alkali, Dr Gosse remained exposed to the fumes for half an hour without inconvenience.

In 1816, one of the inspectors of health of the city of Paris invited Dr Gosse to make a trial of the efficacy of his sponge mask and spectacles. The soil-pit was in a bad state, or plombée, as it is called by the French. Fire had been employed to expel the carbonic acid gas. Two workmen who had gone down successively felt the presence of the mephitism, and could scarcely remain three minutes. They cough ed, had difficulty of breathing, and their eyes were much irritated. Dr Gosse descended after them into the pit, with the sponge soaked in a solution of sugar of lead, and his ears stopped with a little moist cotton, and although he stirred up the soil with a shovel, he remained a quarter of an hour without inconvenience, or having his breathing affected. The smell of the sulphuretted hydrogen gas was destroyed, and his eyes even were not affected either by it or the ammoniacal vapours. He made a second trial of his apparatus in another soil-pit, which the workmen had been obliged to desert the evening before, notwithstanding fires were constantly kept up. The morning that Dr Gosse made his experiment in it, three workmen had been drawn out of it with ropes in a state of commencing asphyxia. He descended without taking the precaution of putting cotton in his ears; and to identify his situation as much as possible with that of the workmen, he tried to work himself. But the labour, to which he was not accustomed, united to the keenness with which he performed it, and the heat of the place, caused a good deal of suffering, and he was obliged to rest two or three times. He had been in a quarter of an hour, when, in stooping, his mask came off, and he could not replace it exactly. Soon after the ac

VOL. I.

cident, he felt a slight giddiness, and he attempted to cry for help and reach the ladder, but he fell back suffocated. He was immediately drawn up, and recovered his senses when he got to the open air. The accident which occurred in this last experiment was entirely owing to the displacing of the mask, and is rather a confirmation of its efficacy, especially in cases where it is not necessary to remain long in such pits. It is on this account that Dr Gosse particularly recommends the use of his masks to those who descend into foul air to attempt to save others who are already overcome by it.

From my own experience I can testify that these masks can be worn without any inconvenience; and I would have no hesitation to expose myself, when protected by one of them, to the most noxious fumes. I therefore feel a pleasure in making known in this country of manufac tures, in which Sir H. Davy's life-preserver has proved of such inestimable value, the discovery of an ingenious foreigner, which will be found also an efficacious life-preserver in dangers of a different kind.

Edinburgh, Sept. 1817.

ALIENUS.

EXTRACT OF A LETTER FROM COUNT MONTLOZIER, AUTHOR OF THE MINERALOGY OF AUVERGNE, ON THE MINERALOGY OF THE NEIGH BOURHOOD OF EDINBURGH.

It is only since I visited Edinburgh that I have been able to form a true conception of the nature of the mountain rock I had so often heard of under the name Whinstone, and to which the denomination Greenstone has been in my opinion improperly applied. It differs from greenstone in formation, greenstone being entirely primitive, whereas whinstone is of a secondary formation: Further, it associates with limestone, coal, and sandstone, minerals with which greenstone is not connected. Calcareous spar, too, forms an ingredient of whinstone, but not of greenstone; and, lastly, greenstone is scratched with difficulty with the knife, but whinstone easily. The whinstone of Scotland appears to be a Neptunian production. It does not occur in the volcanic regions of Auvergne, in the Vivrais, in Italy, nor, in general, in Germany, but it has a resem

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