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could in this case give to medicine, and it constituted nearly all in the way of special remedy which the physician was able to employ. The cause and seat of the disease were alike unknown. A sudden glimmer, however, appears to have been thrown upon the subject through an observation by M. Bernard,—that if a slight wound be inflicted upon the fourth ventricle of the brain, a little above the origin of the eighth pair of nerves, the pneumo-gastric, which proceed among other organs to those of digestion, the urine becomes charged with sugar, and presents the other characters usual in diabetic disease. The study of chemical symptoms, therefore, must be combined with that of the chemical functions of the different parts of the body, and of the derangements of those functions which almost insensible lesions may occasion. How curious, that in a malady where both departments of science are called in, chemistry should almost exclusively fix the attention upon the urine, while physiology bids us turn our efforts chiefly to the condition of the brain! It will readily occur to some of our readers that M. Bernard's observation, if fully established, communicates directly with many other most interesting questions still open to discussion, such as those which relate to the true theoretical action and real practical effect of substances employed as food for man and other animals.

Intimately connected with inquiries such as those we have been noticing, is Sanatory Chemistry,—a subject very popular in its nature, wide in its extent, important to all classes of society in every country, and yet unfortunately but little understood, and until recently as little appreciated. The composition of the atmosphere, -- the nature, needs, and effects of healthy respiration, — the properties and influence of injurious gases and exhalations, — the constitution and wholesome chemical and other influences of the sun's rays, — the priceless value of pure and abundant water, — the impurities of wells in towns,— the blessings which attend upon cleanliness of person, and in our streets and dwellings, these are some of the comprehensive questions which this division of scientific inquiry includes, and into which chemical investigation is daily making way.

Then Forensic chemistry brings us into close contact with questions of law and the controversies of the courts. What is called Medical Jurisprudence includes only a part of forensic chemistry, and yet it boasts the elaborate treatises of Orfila, Christison, Taylor, and Beck, besides many valuable German works, and countless minor books and dissertations. Cases of poisoning form the staple branch of this department. They have recently been of unusual frequency in England, and in some instances of so wholesale a character as forcibly to arrest

1851.
Forensic Chemistry.

289 the attention of the public, and to call for legal restrictions on the sale of poisonous substances.

The introduction of a bill by Lord Carlisle for this purpose, and its subsequent passage in the present session of Parliament, has recalled to our mind a state of things which existed in Normandy a few years ago, the cause and cure for which may suggest the adoption of other measures of prevention among ourselves also, in addition to the legislative measures already passed into a law. In Normandy, it had long been the practice, as it still is in some of our southerly English counties, to use white arsenic for the steeping of seed corn, with a view to the destruction of insects and fungi - as the midge, smut, rust, &c. — by which grain crops are frequently very much injured. This abundance of arsenic among the people, and their familiarity with its use, brought every season before the courts, from the rural districts, a yearly crop of poison cases, in which arsenic had been employed for the destruction of human life. With a view to provide a remedy, it was at first remitted to the Departmental Society of Agriculture, to inquire whether this use of arsenic was indispensable, and whether in the chaulage du blé other substances of a less dangerous character might not replace it both effectually and economically. The experiments made by direction of the Society enabled them to report that arsenic might be dispensed with, and that less deadly substances were as cheap and efficacious. A law was passed in consequence, forbidding the use of arsenic in the preparation (pickling) of seed corn, and the annual group of poisoning trials disappeared. If, as we believe, it is chiefly in those parts of England where arsenic has been so employed for agricultural purposes, that our home poisonings with it have also been most frequent, the abandoument or prohibition of it in the farm might not only remove in some cases the means and direct temptation to crime, but might in others take away also a source of evil suggestions which afterwards lead to the purchase of poison for otherwise unthought-of ends.

· How oft the sight of means to do ill deeds

Makes ill deeds done ! Forensic chemistry, besides such questions as properly engage the medical jurist, embraces also a crowd of inquiries, almost endless in variety, connected with the validity and alleged infringement of patents, with the adulteration of substances liable to duty for the purpose of defrauding the revenue, with the creation of nuisances, or with the injuries produced by manufacturing operations. It is also more or less directly interested in all those adulterations of articles of domestic consumption,

VOL. XCIV. NO. CXCI.

by which the health and comfort of the people are liable to be affected, and against which the public are driven to seek protection in courts of law. Upon these topics we cannot dilate. But such of our readers as feel an interest, especially in regard to the instances we have mentioned last, will consult with advantage the excellent manual which Dr. Adolf Duflos has dedicated to this vitally important subject. *

The small remainder of our space is due to the consideration of general chemistry as an aid to industry, both individual and national. And here, taking the more comprehensive works of Schubarth or of Knapp, as our guides, we might illustrate by a thousand special cases the direct money value of chemical knowledge, and even of profound chemical research, to the material prosperity of a country like our own.

In its application to the arts of life, indeed, almost as easily as in any other way, the progress of this science can be palpably made manifest to the most ordinary understanding. If the older work of Aiken on the Chemical Arts be compared with the later Dictionary of Dr. Ure, or the treatise of Dumas, and these again with the still later German publications, it will be seen not only that all the separate arts known to the older author (Aiken) have been greatly improved — old difficulties, delays, and expenses removed by the discovery of new methods — but that numerous new arts are described, which in the interval have sprung into existence and assumed a more or less important place among the sources of national or local wealth. And further, by a comparison of the newest work on Chemical Technology with the one immediately preceding it, the rate of progress at the present moment will be found to be more rapid than at any previous period in chemical history.

Or a person less conversant with books, but who takes some interest in the matter, may arrive at the same result in another way. If, bearing clearly in his mind what he had seen during a pains-taking visit to the workshops of London, Birmingham, Sheffield, Manchester, or Glasgow, some thirty years ago, be should now again revisit these centres of industry and attempt to compare their present with their past processes and products, the change would appear absolutely wonderful. The new, more

* Die wichtigsten Lebens-Bedürfnisse, ihre Aechtheit und Güte. Breslau: 1846. Now that coffee and chicory, and wheaten flour, and so many other articles of daily use are the subjects of countless adulterations, a book like that of Duflos's, but adapted to our circumstances, has become a want in English literature. Since Accums' ' Death in the Pot,' we have had no special book devoted to this subject.

1851.

Application of Chemistry to the Arts.'

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speedy, and simpler modes of arriving at the same results — the numerous subdivisions of labour, elevating what were probably regarded as mere processes of detail, into separate manufactures and branches of business -- the multitude of new and totally distinct arts and workshops — the new intellectual resources which even common men seem now to have at easy command — and the new uses to which the waste materials of former years are now applied,—these will astonish him almost as much as our machine shops, in which the fingers of the dexterous workman appear to persuade rather than compel the inert material to do his bidding, until the dead metal seems fashioned to do something little less than think. .

To watch from year to year the details of improvements like those which our visitor would recognise, is one of the most interesting occupations of the scientific observer. Difficulties bring out resources. Even apparently insurmountable crises in a manufacture only stimulate the energies of the conquering intellect. An important branch of industry appears about to succumb — to shift its locality at least, and take up a more favoured home in another country, when chemistry suggests that its work should be done after a new fashion. The suggestion is adopted, and the greater perfection and economy which attend the change, give the old locality a fresh start, and secure to the failing manufacture fresh triumphs over dreaded rivals.

A change in fiscal regulations, the competition of slave labour and other causes, have threatened to root out the growth of sugar from our West India colonies. But a chemical experiment, made in Brussels by Melsens, suggested to him improvements in the treatment of cane juice, which promise to give to capital and skilled labour in this branch of industry the same victory over mere manual toil, which in all other arts they have gradually been acquiring. Again, the progress of the art of spinning had not only enabled the cotton machinery to produce threads of a fineness which Indian beauties never dreamed of, but the costliest linen cambrics of Holland and Flanders were already surpassed by the produce of our native looms. The machinery of the flax mills, however, had exhausted its skill upon the stubborn material, which refused to stretch to a more subtle fibre, or produce a finer yarn. But chemistry examined the substance by which the fibres are naturally held together; and forthwith spinning by the aid of steam heat compelled the glutinous matter to relax its hold and the delicate fibres to slip along each other into threads of previously unattainable tenuity. The steeping of flax too was a tedious process, pregnant with nauseous exhalations and with frequent disease. For ages par

ticular streams were famed for their efficacy in steeping, and particular localities enjoyed centuries of reputation for their unspun flax. The fineness of the fibre depended on the plant being neither full grown nor rank: and it was held impossible to grow to a profit both seed and stem at once. But a new mode of steeping has been devised by Schenk owing to a chemical discovery. This invention has shortened the process to a few hours; has placed all localities on an equal level, by making all tolerably pure waters equally available; has abolished the yearly nuisance and frequent disease; has extracted the finest fibre from the rankest and ripest plant; and has thus placed within the reach of the farmer and of the country the double profit of a full crop of ripe seed, along with a heavy harvest of luxuriant stems. Even upon this improvement further improvements are already spoken of, and a rival patentee is threatening to supersede, by the employment of steam, the hot water employed in the process of Schenk. Further, a cloud was approaching the factories of Lancashire. Cotton, the growth of a rival country, it is feared, might become scarce, and rise in price, - consequences which would seriously embarrass our staple manufacture. Another chemical process here steps in, tears still further in pieces the single hollow fibres of the flax, and produces a material which resembles cotton in appearance, can be spun with the same machinery, and according to the discoverer, M. Claussen, may in all probability be brought into the market at a price low enough to compete successfully with natural cotton. Thus a new material is likely to be supplied to our home manufactures, and at the same time a boundless field opened, and a new stimulus given, to our home agriculture – a new bond, in fact, created between the already inseparable interests of our town and country communities. M. Claussen already speaks of larger orders than can be supplied.

As in this way the science of chemistry has lent itself to the advancement of one art, so it has done with a thousand others.

The paper on which we write - the child of waste flax and cotton fabrics —- tells us daily of its obligations to chemical research. The discovery of chlorine gave a method of removing all colour from tissues which had been dyed or printed with vegetable or animal colours. It thus widened the sources of the supply of his raw material to the manufacturer, and kept down the price of paper to the consumer, while the demands of the press and the post office increased.* Then, after numerous adjustments

* We have before us a literary curiosity which indicates another direction into which the scarcity of material guided the research of

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