more serious of the special results which are now observed to occur to victims of absinthe, though the habitual drinking even in small doses of good absinthe, is believed by Dr. Decaisne sooner or later to produce disorders in the human economy. Now, various deleterious substances are added, the most important of these being antimony. As at present constituted, therefore, and especially when drunk in the disastrous excess now common in Paris, and taken, as it frequently is, on an empty stomach, absinthe forms a chronic poison of almost unequalled virulence, both as an irritant to the stomach and bowels, and also as a destroyer of the nervous system. The effect of absinthe is to produce a superabundant activity of the brain, a cerebral excitement which at first is agreeable; intoxication comes on rapidly; the head swims, and the effect produced is nearly the same as that of poisoning by a narcotic, which certainly does not occur with an equal dose of brandy. With the absinthe-drinker, as with the opium-eater, the excitement the spirit produces diminishes daily in intensity. Each day he is obliged to augment the dose in order to bring himself up to the right pitch. The diseases brought on by the excessive drinking of ardent spirits are produced with greater rapidity by the use of absinthe. The amount of absinthe consumed in London has during the last few years been enormously on the increase. Acarus Farinæ, or Flour - MiteThis insect is found only in damaged flour, and is more frequently met with in the flour of the Leguminosa than that of Gramineæ. A single acarus may occasionally be found in good flour; but even one should be looked on with suspicion, and the flour should be afterwards frequently examined to see if they are increasing. It differs considerably in structure from the Acarus sacchari. Acarus Sacchari, or Sugar-Mite Found in nearly all the brown sugars of commerce, and is in size so considerable that it is plainly visible to the unaided sight. It may always be detected by the following proceeding: Two or three drachms or teaspoonfuls of sugar should be dissolved in a large wine glass of tepid water, and the solution allowed to remain at rest for an hour or so; at the end of that time the acari will be found, some on the surface of the liquid, some adhering to the sides of the glass, and others at the bottom, mixed up with the copious and dark sediment formed of fragments of cane, woody fibre, grit, dirt, and starch granules, which usually subside on the solution of even a small quantity of sugar in hot water. The Acarus sacchari, when first hatched, is scarcely visible, and first appears as a rounded body or egg. This becomes elongated and cylindrical, until it is about twice as long as broad. After a time the legs and proboscis begin to protrude. The body is partially covered by setæ, and the feet terminate in hooks. In its perfect state its structure is as follows: The body is oval, or rather somewhat ovate, being broader behind than before. From its posterior part four long and stiff bristles proceed, two together on each side, and some eight or ten smaller ones are arranged nearly at equal distances around the circumference of the body. From the anterior part a proboscis of complex organisation proceeds, and from its inferior surface eight legs, jointed and furnished with spines or hairs at each articulation. The spine which issues from the last joint but one of each leg is very long, and extends much beyond the termination of the leg itself. In most samples of sugar the acari may be seen of all sizes, that is, in all stages of their growth, and in every condition. In sixty-nine out of seventy-two samples of sugar examined by Dr. Hassall sugar acari were found. Acarus Siro-Acarus Domesticus, or Cheese-Mite —A very small insect, scarcely perceptible without the aid of the microscope, found in decayed cheese; in fact, the dry and powdery parts of cheese consist almost entirely of these acari and their eggs, in different stages of development. The eggs of this insect are hatched in about eight days. The Acarus siro is furnished with a peculiar elongation of the snout, forming strong-cutting, dart-shaped mandibles, which it has the power of advancing separately or together. They appear to be able to retain life for a lengthened period though deprived of food. Leewenhoek informs us that one lived for eleven weeks gummed on its back to the point of a needle. When kept without food, it is no uncommon sight to see them killing and devouring each other. Cheese is rapidly destroyed by them; they crumble it into minute pieces, and emit a liquid substance which causes the decayed parts to spread speedily. Exposure to a strong heat quickly kills them, or plunging the cheese in whisky will have the same effect. Acetic Acid-See ACID, ACETIC. Acid-The popular everyday signification of this word means anything which is sour to the taste. Scientifically speaking, acids are definite chemical compounds, which unite with alkalies, form bases, and redden vegetable blues. They are now generally considered salts of hydrogen; thus, sul phuric acid (H.SO.), hydrochloric acid (HCl), | though the local action is more severe, it is nitric acid (HNO3), are called respectively less extended. the sulphate, the chloride, and the nitrate of hydrogen. In a public-health sense they are chiefly interesting as being emanated in the process of various manufactures, and then acting injuriously both on vegetation and man. Besides this, most of the more common ones are to a degree disinfectants, and many of them have been, by accident or design, used as poisons. The gases evolved from manufactures of alkali used to contain so large a proportion of hydrochloric acid, that it had a most injurious effect on the vegetation of the surrounding district; so much so, that an Act was passed for the more effectual condensation of such gas in alkali-works (26 & 27 Vict. c. 124). This Act, in the first instance, was continued to the 1st of July 1868; but by 31 & 32 Vict. c. 36, s. 1, it has been continued without limitation to time. A section of the Act provides for the appointment of an inspector of such works by the Board of Trade. (See ALKALI ACT.) Now this acid is so effectually condensed that the air emitted from the flues hardly makes a solution of nitrate of silver turbid. The fumes from hydrochloric, sulphuric, sulphurous, nitric, and nitrous acids are quite irrespirable if attempts are made to inhale them in an undiluted form. Diluted well with air, as in some processes for making steel, they appear to irritate the lungs greatly, and have been said to cause pneumonia, bronchitis, and phthisical ulcerations of the tissue of the lungs. Amongst bleachers, and various workers in wool, bronchitis prevails, and the men look sallow and anæmic. This effect has been ascribed to the sulphurous acid disengaged. The effect of acids on vegetation is a subject of practical importance, especially in relation to the question as to whether a manufactory is properly condensing its gases, or whether it is not injuring the surrounding country. The distance at which an acid-emitting manufactory has been found to injure vegetation is about 2187 yards; prevailing winds may, however, carry the vapours farther than this in particular directions; slight undulations in the ground, hedges, walls, belts of trees, and similar obstacles, modify and obviate the action in such a manner as to lead to the conclusion that the gas does not mix uniformly with the air, but is absorbed in small globules of water, which are thrown forward by currents of wind or air, and are driven over any wall or interruption to a distance in a curve from the top.-(ANGUS SMITH.) Rain washes acid gases down to the earth quickly; so that, The effect of acids on the vegetation is to be judged of by the general appearance of the plants, shrubs, and trees in the vicinity. The sources of error in this investigation are numerous, and are more especially due to the fact that dry cold winds, fungi, and insects, produce many spots and changes in leaves and plants similar to those from corrosive vapours. Acids shrivel and curl up the leaves, but do not, like winds, break the stalks, and render them ragged. The coloured spots on the leaves may be tested with litmus paper; but care must be exercised and careful comparisons instituted between the same leaves from healthy plants. Dr. A. Smith says, indeed, that many plants contain chlorides, even on the surfaces of the leaves, at a great distance from alkali-works. Mr. Rothwell affirms that in fields exposed to acid vapours, handfuls of dead grass may be pulled up in the spring, smelling strongly of the vapour, and that trees, under similar influences, become bark-bound. Dr. A. Smith gives, in his work on "Air and Rain," the following list of trees, in the order in which they are affected, on Mr. Rothwell's authority: Old grass meadows and pastures receive much serving animal and vegetable substances and damage in the winter. As Disinfectants.-All the mineral acids are powerful if poured upon putrid matter, because they destroy it; but they are hardly suitable for common use, on account of their irritating nature to man. In 1773 Guyton Morveau wrote a large volume recommending muriatic acid as a disinfectant, and Dr. Carmichael Smith used nitrous acid at Winchester in 1780. Sulphurous acid is of real value, and has been used from the most ancient times as a disinfectant and fumigator. (See SULPHUR.) Of the organic acids, vinegar, or impure acetic acid, still deservedly retains some repute as a disinfectant; yet it is only a weak agent, at all events a poor protection against the germs of disease, for in vinegar itself infusoria and vegetable organisms develop. Most stinks are in all probability compound ammonias, at all events the odorous gases of this nature usually have an alkaline reaction; therefore vinegar or other acid fumes probably neutralise them. The most valuable of the acid disinfectants are, however, carbolic and tar acids. The acids that have been used accidentally or designedly as poisons are sulphuric, by drochloric, nitric, arsenic, and phosphoric among the mineral; oxalic, meconic, prussic, and a few others, among the organic acids. The most important of these will be considered under their respective heads. The antidotes for poisoning by the mineral acids are chalk, magnesia, white of egg, oil, &c. anatomical preparations; it is also much employed in the arts, manufactures, and for medicinal and other purposes. Acid, Benzoic-(HC,H,O,)—This acid is usually obtained by subliming it from gum benzoin; occasionally by dissolving it out from the gum by means of an alkaline liquid. Its principal adulterations are-hippuric acid, detected by its diminished solubility in water (1 part of pure benzoic acid is soluble in 300 of water), by its exhaling the odour first of the tonquin bean, and then of prussic acid; succinic acid, recognised by the solubility being increased; sugar, detected by the odour of caramel, and the black and carbonaceous residue-while pure benzoic acid sublimes. Camphor and spermaceti are also used, and may be detected by the odour, and other well-known properties. Aoid, Caffeic-According to Vlaanderen and Mulder, the formula for this acid is tained from coffee. The dry berry contains C1HO7. It is an astringent principle obabout 5 per cent. of it. Acid, Camphoric― (H2C10H104) — Obtained from the oxidation of camphor by nitric acid. See CAMPHOR. nylic Acid) — (HC,H,O.) — Sp. gr. Acid, Carbolic (Phenic Acid), (Pheof (35° C.); boiling-point, 369° (187° C.) This liquid, 1065; fusing-point about 95° F. substance, when pure, is in crystals in the form of long, colourless needles. It is obtained from coal- tar. The commercial acid is, roughly speaking, of two kinds : one a cheap liquid, varying from a light-brown to a very dark, almost black, liquid; and Calvert's carbolic acid, which is in beautiful white crystals, and is used for medicinal and other purposes. Acid, Acetic-(HC2H3O2) - Sp. gr. Properties.-The crystals, when pure, are 1063. This acid derives its name from white; but in keeping frequently become pink, acetum, vinegar. It exists naturally in the sap rose, or crimson. It has a powerful tarry of the oak, and in other plants. It is usually odour, and a very small quantity of water obtained from the destructive distillation of serves for its liquefaction. The crystals are wood, or from the oxidation of alcohol. (See very sparingly dissolved in water, but they VINEGAR.) The acid is often adulterated with are freely soluble in alcohol, acetic acid, and water, sometimes sulphuric acid and lead-ether. With bases the acid forms phen ates or carbolates - e.g., carbolates of lime, | is of inestimable value. Mr. Crookes investipotash, &c. A slip of deal moistened with carbolic acid, and then dipped into hydrochloric or nitric acid, turns in drying to a blue colour. A drop of the acid leaves a greasy stain on paper, which is, however, transient. Solutions of the acid do not redden litmus paper. The most important properties of carbolic acid are its disinfectant and antiseptic powers. Of late years it has taken its position in popular estimation as the best practical deodoriser and disinfectant for drains, putrefying matter, &c. &c.; and as a preventive of disease it has been placed in nearly all the urinals and waterclosets of railway stations, in the hospitals, barracks, and other public places in the kingdom. It is invariably used in all kinds of contagious diseases to disinfect the excreta, and in a diluted form is frequently applied direct to the bodies of persons suffering from smallpox, scarlet fever, &c. Nor has its use been confined to this country. In France, M. Devergie has warmly supported it, and declared it to be the best disinfectant known. He has employed it successfully in purifying the Morgue. This is done by a coutinuous stream of carbolised water, containing 1 of the acid to 4000 parts of water. That it is extremely valuable for these several purposes it is impossible to doubt; that it is superior to every other disinfectant, as some have asserted, may well be questioned. One of the gravest objections is its poisonous character. It is obvious that it is unsafe to drench and saturate all sorts of places with such an active poison as carbolic acid. It certainly does not destroy when in a dilute form every form of contagion. Dr. H. J. Von Ankum, in the "Morandschrift voor Natuurwetenschappen," states that atmospheric air, to which the vapour of carbolic acid has been added, does not hinder the development of lower organisms in water with hay in milk or urine. Experiments have also been made with air saturated with carbolic acid on vaccine lymph, which has, after exposure to this agent for some time, still preserved its activity. This agrees with Pettenkofer's observation,* that carbolic acid preserves inert ferment cells, but they resume their activity upon withdrawal from its influence. In fact, its real action appears to be very similar to that of great cold, the substances are preserved as if frozen. On this account it must be looked upon with suspicion as a disinfectant when any contagious germs are to be dealt with; it may fix them for a time, but does it destroy them? On the other hand, as an antiseptic it * Allgemeine Zeitung, Feb. 4, 1866. gated it with great industry, and found that a solution of 1 per cent. preserved meat, skin, gut, and other substances if steeped in the solution and then dried; it also stopped fermentation, and destroyed gnats, beetles, caterpillars, mites, fish, and infusoria. Angus Smith has recommended it for the disinfection of sewers. M'Dougall has used a mixture of tar oil and lime for this purpose in Carlisle ; and in Leipzig a mixture of chloride of magnesium, lime, and tar has been tried, and found of some practical value. The two principal carbolic acid powders in use here for various purposes are M'Dougall's and Calvert's. M'Dougall's powder is composed of— Carbolate of lime, 33 59 8 100 Calvert's powder consists of carbolic acid (20 to 30 per cent.), alumina, and silica. These powders may be sprinkled about a room, added to sewage, or diffused in water, and applied in solution. In disinfecting cholera or typhoid stools, very strong solutions should be used. See DISINFECTANTS. cerine is a good application to make to the One part dissolved in 100 of olive oil or glybodies of patients suffering from smallpox, scarlet fever, or other disease in which cells or germs are supposed to be thrown off. internally-topically, as an application to the It is used as a medicine both topically and skin in the strong form as an escharotic; and diluted, as a lotion to all kinds of foul sores, skin diseases, &c. Internally it closely resembles creosote in its action, allays vomiting, and is said to be useful in diabetes. During the prevalence of the cattle plague it was extensively used. The appendix to the Royal Commissioners Report on the Cattle Plague contains the following: According to the principles laid down, the air must be treated, and where there is no disease there is only a secondary use in treating anything besides the air. Several cowhouses have been treated with carbolic acid with very excellent results. The mode has been, first, to remove from the floor the mass of manure which too often adheres to it; secondly, to sprinkle the floor with strong carbolic or cresylic acid; next, to wash the walls, beams, and rafters, and all that is visible in the cowhouse, with lime, in which is put some carbolic acid, 1 to 50 of the water used, or with strong carbolic acid alone. Next, to make a solution, containing 1 of carbolic or cresylic acid to 100 of water, or perhaps still better, 60 of water, and to water the yard and fold until the who place smells strongly of the acid. Only a few farms have been treated in this way, so far as I know, but in each it has been successful. It may be well to give the cattle a little of the weak solution of carbolic acid, but this has not been so fully tried as the external use. The washing of the mouth and entire animal with the weak solution may be attended with good results, especially in the early stage of disease; but I know nothing of cure, and speak only hopefully of prevention. The animals seem to have an instinct for disinfection, and lick substances touched with this acid. They must not be allowed to drink it, as when strong, as already said, it blisters the skin, and especially the mouth and tongue. Mr. Crookes gives the results of his experiences as follows: It appeared evident that if harm were to follow the injection of carbolic acid, the mischievous effect would be immediate; but that if the fluid could pass through the heart without exerting its paralysing action on that organ, and could get into the circulation, no present ill effects need be anticipated. I therefore determined to push these experiments as far as possible, increasing the quantity of carbolic acid until it produced a fatal result. The next operation was on cow No. 11, in which 3 ounces of solution (containing 524 grains of pure carbolic acid) were very slowly injected: no bad effect followed, Increasing the dose, cow No. 12 had injected into her vein 4 ounces of solution (equal to 78 grains of carbolic acid); this also was followed by no immediate ill effect. Cow No. 13 was then treated with 6 ounces of solution (containing 105 grains of pure carbolic acid), in two portions of 3 ounces each, five minutes' interval elapsing between each injection. The first 3 ounces produced a slight trembling, but not so severe as in the case of cow No. 10, as she seemed better in a few minutes. The second dose of 3 ounces was injected. This proved too much, or was pumped in too hurriedly; for almost before I had finished, the animal trembled violently, its eyes projected, its breathing became laborious, it fell down and expired. The result could scarcely be attributed to the accidental injection of air into the vein, for the distress began with the injection of the first syringeful, and was only increased by the second; nor is it likely that this accident would happen twice consecutively. I was particularly careful on this point, and the construction of the instrument rendered such an occurrence scarcely possible with ordinary precaution. It is probable that the injection was performed too rapidly, or that the vital powers were lower than usual. In the case of the remaining animal, No. 14, I decided to inject as large a dose as it would bear, stopping the operation at the first sign of trembling, and delivering the liquid very gradually. The first syringeful caused no bad symptoms, and I had just finished injecting the second dose when trembling commenced. It was rather violent for a short time, but soon went off, and in five minutes the animal appeared as well as before. This cow, therefore, bore without inconvenience the injection of 6 ounces of a 4 per cent. solution, containing 105 grains of pure carbolic acid. Careful observations with the thermometer were taken before each operation. There were no more diseased beasts on the farm, or I should have carried my experiments still further. On visiting the farm the next day, I was told that all the animals seemed better; and on testing them with the thermometer that statement was confirmed. I gave directions that each animal was to be drenched with half a wine-glassful (1 ounce) of carbolic acid in a quart of warm water every morning, but in other respects they might be treated as Mr. Tomlinson, a skilful cow-doctor, should direct. Business now calling me to London, I was unable to watch the further progress of these cases. This is to be regretted, as a series of daily thermometric observations would have been of great value in suggesting further experiments. I had, however, frequent accounts sent me. Cow No. 14 continued to improve slowly until convalescent; she is now quite well. Nos. 10, 11, and 12 remained in apparently the same state for four days; they then changed for the worse, and died. It is not improbable that, had I been able to inject a further quantity of carbolic acid during the four days in which they were thus hovering between recovery and relapse, it would have turned the scale, and some of them, at all events, would be now alive and well. The following table gives the thermometric observations: If future experiments prove that injection of car. bolic acid or other antiseptic will do good, it is an operation very easily performed. I have injected five animals and taken thermometric observations within an hour. Sulphite or bisulphite of soda apparently occasions some pain, as the animals struggle very much; with carbolic acid I found them tolerably quiet. I have calculated the proportion which the carbolic acid bore to the whole quantity of blood in these operations. Taking the whole amount of blood in the animal at 150 pounds, there were injected into |