Adulteration, a term applied to the deterioration of different articles of food, drugs, etc, by mixing them with cheap and inferior substances. The microscope has become a very important instrument in detecting fraudulent mixtures. In wheat flour it detects the mixture of rice flour, and in the maranta arrowroot it exposes the peculiar structure of the cheap potato flour and sago. In mustard and coffee it brings out the peculiar forms of chic-cory root; and in the former turmeric has been detected by it, when this was added only in the proportion of 1/500 part. Poisonous ingredients, being mostly of a mineral nature, are subjects rather of chemical analysis than of microscopic examination. There is an instance, however, of cattle having been poisoned by eating rape or oil cake, in which were detected by Dr. Hassall the ground seeds of the mustard. Chemical analysis in such a case could discover nothing. It is to Dr. Hassall, the author of scientific papers in the London "Lancet," and of several works on food and its adulterations, that the credit is principally due for the progress made in this department of science, at least in its applications to this subject. In some vegetable powders, Dr. Hassall has succeeded in detecting nine different vegetable productions.

The mineral poisons that are made use of to give light colors to confectionery, and the fine green shades to pickles and to tea, are only brought to view by chemical analysis. By these, however, they are separated quantitatively, and in forms that are recognized by every one. The mistaken taste of the public for very white bread leads the baker to select the flour from which the more nutritious portion of the grain has been separated by the miller, and to make this flour still more white he adds to it a quantity of alum. Though the use of this substance in bread is forbidden by law in England, it was found in every one of 53 samples that were examined for it. Cheaper and less nutritious kinds of flour, as of rice, potatoes, corn, beans, rye, etc, are mixed with wheaten flour, some of which, besides their direct effect in lessening the value of the article, also cause the bread to absorb much more water, and thus add to its weight by substituting water for flour. Carbonate and sulphate of lime, silicate of magnesia in the form of soapstone, white clay, carbonate of magnesia, bone dust, and bone ashes, have all been detected in flour in England. In the adulterations of tea, especially green tea, the ingenuity of the Chinese is taxed before it leaves their country, and that of the English on receiving it in their own.

The list of other plants which furnish leaves for the tea chests, and which are recognized by the microscope, is too long for repetition here, and so of the poisonous mineral ingredients, including arsen-ite of copper, which are skilfully used to make good green teas of unsalable black teas. Coffee fares somewhat better, its adulterating mixtures being of a more harmless nature, such as chiccory, acorns, mangel-wurtzel, peas, and beans, and for the use of the poor in London roasted horse liver. In an analysis made in 1872, under the direction of the Massachusetts board of health, a pound package of a mixture sold as ground coffee was found to contain no coffee whatever; but coffee sold in bulk was nearly always found pure. Sugars are more decidedly free from adulteration, but the brown sugars, as usually imported, are found from the accidental impurities present, and from the im-mense numbers of live animalcules, to be in a state unfit for human consumption. The white lump sugars are very pure, and any insol- , uble substance like sand can be easily detected. No articles, however, have been the subjects of such a reckless system of adulterations as the colored sugar confectionery.

Though expected to be used principally by children, the colors painted upon the candies and sweet-meats are the product of virulent mineral poi-sons; and it is wonderful what a variety of these have been made applicable to this purpose. Their use, however, is not now nearly so great as it was in former times, and is discountenanced by reputable dealers in these articles. - Wines and spirits, from their high value and general use, as also from the diffi-culty of detecting the cheap mixtures added to them, are almost universally adulterated to some extent; while many are made up en-tirely of ingredients wholly foreign to the country which produces the genuine wine. The substances added with a view of preserving wines are sometimes poisons, lead and copper both being used, the former in the state of litharge. In England the favorite port wine i is thus most shamefully treated, besides being manufactured on a very large scale, after a variety of curious recipes, from thousands of pipes of spoiled cider imported for the purpose, bad brandy, and infusions of logwood and other dyestuffs.

The champagnes, which are more in demand in this country, find here as ingenious imitators; and from our native ciders, with a due mixture of cheap French wine, sugar, brandy, and a little lemon or tartaric acid, more champagne is bottled than ever crosses the Atlantic. If gooseberry wine is easily obtained, it is used instead of cider for making good champagne. The impossibility of supplying the' demand for French brandy, and the consequent high price of the article, have led to its extensive manufacture in France from very cheap materials. These materials are water and spirits obtained from molasses, beet root, and potatoes, and more particularly cheap whiskey, which is sent from this country in large quantities to come back brandy. Burnt sugar gives the desired color, and the fine flavor is made to suit the taste by skilful admixtures of essential oils and distilled murk, which is the refuse skins and pips of the grape left after the wine is expressed. This stuff is imported into England, to be distilled with molasses for making brandy. Gin is largely adulterated with water, and as the effect of this is to make the liquor whitish and turbid, other substances must be added to correct this and "fine " the gin. These are alum, carbonate of potash, and the poisonous acetate of lead.

To restore its strength and pungency, cayenne in the form of tincture of capsicum, or grains of paradise, are employed; and its peculiar aroma is preserved by compounds called " gin flavorings," the ingredients of which are juniper berries, coriander seeds, almond cake, angelica root, licorice powder, calamus root, and sulphuric acid. The common whiskey of the country is largely diluted in the distilleries with water, and then to restore the strength the lye of ashes, which is prepared for the purpose, is added in sufficient quantity to give the liquor the character which is expressed by the slang name by which it is called of " rot-gut." The report of the Massachusetts board of health, already referred to, shows that the adulteration of vinegar with sulphuric acid is extensively practised, especially in wine vinegars. Lead is also found in vinegar, often coming from lead faucets. - It has been supposed that the adulteration of drugs was very generally practised, and almost without check. Were this the case, medicine would indeed be in bad repute; for in no department would this practice be followed by more disastrous consequences.

That it is largely adopted, the analyses of our most respectable druggists prove; but these also show that the system may be exposed, and in a great measure checked, by those disposed to do so; and further, that the articles used for sophistication are generally of a very harmless nature. In July, 1848, a law went into effect in this country, forbidding the importation of these dangerous mixtures. But while the effect of this has been to exclude foreign adulterations, the manufacture of them at home has been greatly increased. In the first year after its establishment, it appears by the report of Dr. J. M. Bailey to the New York academy of medicine that over 90,000 pounds of drugs, comprising Peruvian bark, rhubarb, jalap, senna, and various other kinds, had been rejected and condemned in the ports of the United States. It is very questionable, however, among druggists, whether after all the sale of spurious medicines has been seriously diminished. The adulteration of Turkey opium is carried on as a regular business at Marseilles. It is there literally made over again. The greatest variety of impurities are introduced into it; besides extracts of the poppy and other plants, sand, ashes, gums, aloes, small stones, pieces of lead and iron, seeds and stems of plants, are freely used.

In England the same practice has been so successfully pursued, that what appeared to be the best Turkey opium has proved entirely destitute of the active principle of the drug. The essential oils, used more particularly for perfumery, are especial objects of adulteration. Oil of wormwood, we notice upon the test book of one of our most respectable druggists, " warranted pure from Boston," contained about 40 per cent, of a mixture of chloroform and alcohol, besides some resin or fixed oil. Such adulterations may be detected by the greatly reduced boiling point of the fluid. Scammony, which is extensively used as a drastic purgative, was before the passage of the law always very impure. At Smyrna its adulteration is still a regularly established business. The article called cake scammony, bought and sold in this country, is considered good if it is found to contain 20 per cent, of the genuine material; and virgin scammony passes if it contains no more than 20 per cent, of foreign matter. This is usually starch.

Chalk and flour are also used.