Popular Science Monthly/Volume 16/March 1880/Popular Miscellany

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POPULAR MISCELLANY.

Action of Organic Acids on Minerals.—At a recent meeting of the New York Academy of Sciences, Professor H. Carrington Bolton, of Trinity College, Hartford, communicated the results of a continuation of his researches on the behavior of minerals with organic acids. In a previous paper (read in 1877) he gave the reactions of ninety-five minerals with citric acid; in the present paper he extended the investigation to two hundred species. Dr. Bolton stated that citric acid has a power of decomposing all classes of minerals little less than that possessed by hydrochloric acid, and that this very difference in degree gives the organic acid an advantage over the mineral acid in the determination of species. Besides treating the minerals with a saturated solution of citric acid, he examined the action of the same solution, to which solid sodium nitrate is added. This mixture proves to be a very powerful solvent, dissolving bismuth, antimony, arsenic, copper, lead, tin, mercury, and silver, and nearly all the natural sulphides. The addition of solid potassium iodide to the solution of citric acid also greatly increases its decomposing power. Applying these reagents to minerals, Dr. Bolton obtained the following results: 1. Complete solution of carbonates, with liberation of carbonic-acid gas. 2. More or less complete decomposition of oxides, phosphates, etc. 3. More or less complete decomposition of sulphides, with liberation of sulphuretted hydrogen. 4. Decomposition of sulphides, with oxidation of the sulphur. 5. Decomposition of silicates, with separation of slimy or gelatinous silica. 6. Decomposition of certain species, with formation of characteristic precipitates. 7. Wholly negative action. The exact behavior of each of the two hundred minerals was given in a printed table, copies of which the speaker distributed to the audience. The application of this investigation is twofold: 1. The utility of the methods in field-work, owing to the portability of the reagents in a dry state; and, 2. The relation of these reactions to the geological work of the organic acids of the soil. The latter point is of much importance, and merits further researches.

How Snakes shed their Skins.—Under the title "About Snakes" in this department of our last number, we gave Dr. H. F. Hutchinson's mode of accounting for the way snakes get out of their old skins. Professor Samuel Lockwood, of Freehold, New Jersey, has witnessed the process, and, from a description of it given in his own inimitable style in a late number of "Nature," we gather the following interesting facts, which, as will be seen, do not support the hypothesis of Dr. Hutchinson: A female snake had already begun to cast her skin when Professor Lockwood made ids first observation, but the process was going on very slowly. The skin was slightly torn at the snout, and the head and a little of the neck were denuded. As it separated from the neck it had a sort of "back-creeping aspect"; there was no rubbing against exterior objects, and indeed it looked as if the change going on might be the work of an invisible power. Closer observation showed that there was a systematic alternate swelling of the body at the neck of the skin, thus stretching it, and making a shoulder in front of this neck, each swelling pushing the loosened skin a little backward. As soon as the process reached the larger ribs it went on more rapidly, and in the following way: "Exactly at the place where the skin seems to be moving backward, a pair of ribs expands. This action enlarges or puffs out the body, and by stretching loosens the skin at that place. In this movement both ribs in the pair act at the same time, just as the two blades of the scissors open together. Now comes a second movement of this pair of ribs, in which action the two ribs alternate with each other. One of them—say the one on the right side—is pushed forward and made to slip out of and in front of the constriction made by the swelling, when it immediately works backward, that is, against the neck of the double receding skin. Now the left rib makes a like advance, and in a similar manner presses backward." Thus, for every backward movement of the inverting skin, there are three rhythmic movements: First, the expansion of one pair of ribs; second, the swelling of the body at that spot; and, third, the pushing back of the skin by the alternate action of each rib. "The cast-off skin is presented inside out, so that every scale is now seen on its under or concave side, and this is also true of the eye scales. To all this there is one exception; the last scale of the tail is a hollow pyramidal or four-sided spike. . . . When the shedding has reached this scale a sharp shake of the extremity is sufficient, and the uneverted spike is left inside of its everted skin." The entire process witnessed by Professor Lockwood took only half an hour, but he says that if a snake is in poor health the casting of its old clothes takes longer and is a much more difficult matter.

A New Food-Fish.—Among the many remarkable results given in the last report of the United States Fish Commission is the discovery of a very important food-fish, entirely unknown to our fishermen. It is a large flounder, the Glyptocephalus cynoglossus, and is known in Europe as the pole or craig. But in Europe it is far from being plentiful, and is highly esteemed as having some of the best qualities of the turbot, especially the presence of that delicious gelatinous fat along the fins. Much of the work of the Commission has consisted of dredging in water of various depths. While trawling with a beam at distances from five to ten miles from the shore, the fish was discovered, and in great quantities; so great, indeed, that a fifteen to twenty minutes' drag would sometimes furnish as many as five hundred pounds of the fish. The reason that this fish has not been known hitherto is due to the fact that the beam-trawl, the only apparatus by which it can be taken, is not used by our American fishermen, as it is by those of Europe. The mouth of this large flounder is so small that a hook small enough to be swallowed would not sustain the weight of the fish. There is every reason to expect that this fish will soon take its place in our markets. The Commission have also brought to light new species of food-fishes i. e., of fishes supposed hitherto as only living in the colder waters of Greenland and Scandinavia. These, too, American enterprise will yet bring to our markets; but, to do so, fishing must be carried on two or it may be three hundred miles from the coast.

Improved Method of diving and staying under Water.—The apparatus now in use for supplying air to divers engaged in submarine operations is both cumbrous and unsafe, the air-tube limiting the movements of the diver, and, by its liability to become entangled and crushed, causing a risk that the supply of air for respiration may be cut off altogether. A new method, in which these drawbacks are escaped by dispensing entirely with the air-tube and pumps, has been invented by a Mr. Fleuss in England, and lately exhibited at the Royal Polytechnic Institute in London. Dr. B. W. Richardson was given an opportunity to closely watch its operation, and from his description in "Nature" we glean the following account of the experiments: The peculiarity of the method consists in the diver's taking a full supply of air-food down with him, which dispenses with pumping, no help being needed except a signal-man and cord. Mr. Fleuss is both inventor and diver. He descends into the water in an ordinary diver's dress. It consists of helmet, breastplate, and common water-tight armings and leggings. On his shoulders he carries a weight of ninety-six pounds, and on his boots twenty pounds. A light cord is attached to the helmet for signaling to the person above. Before the mask is closed and the helmet adjusted, an "ori-nasal mouthpiece," with a breathing-tube of an inch bore proceeding downward, is firmly tied over the mouth and nose. Dr. Richardson carefully observed two experiments, one of twenty minutes' length, and another of an hour; and was assured by the diver that when under water he breathed as freely and easily as in the air. This was confirmed by his appearance and condition at the end of the longest experiment. He moved about on the floor of the tank, picked up coins, and could lie down and get up without difficulty. The exact mode by which breathing is effected Mr. Fleuss declares to be extremely simple, though it still remains a secret, but it is wholly carried on within the apparatus, not even the expired air becoming apparent in the water. The facts demonstrate that, without assistance from above, a man who has had no previous experience of diving or remaining under water can take down with him sufficient oxygen to live there easily for an hour; and but for the cold the diver asserted that he could have remained another hour and a quarter, and that he could easily arrange to remain four hours. Depth he said would make no difference as to breathing within the apparatus. Dr. Richardson is enthusiastic over the practical possibilities of the discovery. If a man can thus take his stock of breathing material with him, and live for hours without external access of air, he may extend the field of his industries and investigations into the deep sea, or the most rarefied atmospheres, into mines filled with choke-damp, or amid the suffocating smoke of conflagrations, without fear of consequences.

Suicide of the Scorpion.—The following facts, as stated by Mr. Allen Thomson in "Nature," throw some light on the mooted question of the self-destruction of scorpions. He states that while residing at Lucca, in Italy, he was greatly annoyed by the intrusion into the house of small black scorpions, which secreted themselves in bed clothing and articles of dress. Having been informed by the natives that this animal would destroy itself if exposed to a sudden light, attempts were made to dispose of the pest in the manner suggested. When one was caught it was accordingly confined under an inverted glass until evening, when the light of a candle was brought near it. At this, the scorpion showed great excitement, rushing round the glass with reckless speed. This state lasted for a minute or two, when the animal suddenly became quiet, and turning his tail over its back brought the recurved sting down upon the middle of its head. Soon it became motionless, and in fact dead.

Electricity and Vegetation.—Several months ago M. Grandeau and M. Leclerc described to the Paris Academy experiments on the influence of electricity on vegetation. From these it appeared that flowering and fructification are retarded whenever plants are excluded from this agent. Recently M. Naudin has been examining the subject, repeating the experiments of Grandeau and Leclerc under different circumstances, and with widely different results. He regards the question as a complex one, and far from being yet settled. The influence of electricity on plants is probably modified by the species, by climate, season, temperature, dry or wet weather, degree of light; possibly, also, by the geological and mineralogical structure of the ground. Until we are better acquainted with these obscure conditions of the problem, any conclusion applied to the whole of the vegetable kingdom is premature.

Transmissibility of Human Rabies.—Whether hydrophobia can be transmitted from man to man, or from man to the lower animals, has long been a disputed question, with little scientific evidence on either side; some recent observations, however, by M. Raynaud, in the Lariboisière Hospital, in Paris, would seem sufficiently conclusive to put an end to all uncertainty on the subject. A man was brought to the hospital suffering from rabies, having been bitten by a dog on the lip forty days before. The wound was cauterized two hours after it was made, and no serious apprehensions were felt about the result until a few days before he entered the hospital, when the usual symptoms of hydrophobia appeared. The day before his death, in a quiet interval, he yielded with the best grace to experiments in inoculation which were made with his blood and his saliva. The result of inoculating a rabbit with the blood was negative (as in the great majority of previous cases of inoculation with blood of animals under rabies). But with the saliva it was different. A rabbit inoculated in the ear and abdomen on the 11th of October began to show symptoms of rabies on the 15th, being much excited and damaging the walls of its cage, while it uttered loud cries and slavered at the mouth. Then it fell into collapse and died the following night. The rabbit's body was dissected thirty-six hours after death, and further experiment was made by taking fragments of the right and left submaxillary glands and introducing them under the skin of two other rabbits respectively. These two rapidly succumbed, one on the fifth, the other on the sixth day (becoming visibly ill on the third); neither passed through a furious stage, however, and the predominant feature was paralysis. The important practical result is, that human saliva, such as caused rabies in the rabbit, is necessarily virulent, and would probably have corresponding effects on man; so that it should be dealt with cautiously, and that not only during the life of the person furnishing it, but in post-mortem examinations.

The Agency of Plants in Earth-Building.—The important question of the part taken by plants in earth-building is discussed by Professor Ernst Hallier, of Jena, in a popular essay on "Plants and Man in their Interrelations." The contributions made by the vegetable world to the formation of the crust of the earth are most obviously shown in the beds of peat and coal, the remains of former immense forests and swamps. These formations, remarkable and important as they are. Professor Hallier observes, are far exceeded by the less apparent changes which are effected by the agency of plants. The deposits of freshwater limestones are largely the results of plant-action. Nearly all the streams in calcareous regions bring down carbonate of lime in solution as a bicarbonate. Their waters being charged with carbonic acid or having absorbed it from the air, are by its aid enabled to act upon the otherwise insoluble carbonate of lime, and to take up a quantity of it proportioned to the amount of carbonic acid they contain. This dissolved lime is in its turn converted by the plants which grow in and under the water into stone. All the carbon that is needed for the organic world, animals as well as plants, is obtained through the action of plants in extracting carbonic acid from the air. Plants and those parts of plants which are under water do not stand in direct relations with atmospheric air, but are dependent on the carbonic acid which is held in the water, and, when this is exhausted, on the dissolved bicarbonate of lime. A part of the carbonic acid is taken up from this substance by the chlorophyl-cells, while the other part remains fixed in the lime in the form of simple carbonate of lime. Since the latter is insoluble in water, it is deposited just where it happens to be, which in this case is on the surface of the plant, and this becomes covered with a coating of limestone. Fresh supplies of water bring down new stores of carbonic acid and the dissolved bicarbonate of lime, and the plants continue their work of converting the latter into the insoluble carbonate. Thus the work goes on Unceasingly, and crust on crust of limestone is deposited on millions of small plants. The plants themselves die, wholly incased in stone, but new ones succeed them, and the layers of petrified plants bear in continuous succession a green coating of growing plants. Strata are added to strata, and the limestones grow enormously through the quiet activity of the charæ, mosses, reeds, grasses, and other plants in the water. Fresh-water limestones are thus still in process of formation in all limestone regions. The minor valleys of the Thuringian Valley contain large bodies of soft, fresh-water limestones, in which the forms of the plants to whose action they are due may be plainly recognized, partly in incrustations, partly in impressions, mixed with fresh-water shells and with remains of the trees which once grew on the shore. The material, though soft, has been used in the manufacture of a building-stone out of which cities like Jena and many towns have been built. Rock-building of this kind has been going on ever since there was a growth of plants on the earth, and has during that time played a considerable part in forming the crust of the earth. Other far smaller plants are occupied in building up rocks, in comparison with the work of which, the labor of the plants we have considered may be called insignificant. The diatoms, which live in fresh and salt waters, are the smallest of all organisms. They were once thought to be animals, but are now regarded as plants, and are one-celled structures which have the property of sucking up large quantities of carbonic acid from the water and storing it in their cell-walls. They increase by repeated divisions and subdivisions of their cells, and build up rocks by their simple presence. They multiply with such prodigious rapidity, and the number of their genera and species is so great, that under favorable conditions, as in the shallows and muddy flats of the seashores and in wet places in the interior, they contribute the substance of whole strata by leaving behind them when they die their silicated cell-walls, which become consolidated with the earthy materials into a harder or softer rock-formation. The magnitude of the operations of this kind that are going on in the present epoch is illustrated in the Lüneberg heath, where the diatomaceous formation is more than thirty feet thick. The city of Berlin is built upon a bed of clay of from six to one hundred feet thick, two thirds of the mass of which consist of diatoms. There is a puzzling feature in the life of these diatoms. They contain a coloring matter, diatomin, which is similar to chlorophyl in its properties and in having the power of abstracting carbonic acid from the air and water. It is hard to understand how this power can be exercised where the light does not penetrate. Yet a great mass of the diatom bed under Berlin is living and active, and streets and houses have been disturbed by its growth. The functions which the diatoms perform in the present history of the earth were also exercised by them during the earliest epochs of which we know, and probably in still earlier times.

Intelligence of a Pet Monkey.—A writer in "Chambers's Journal" vouches for the truth of the following story about a pet monkey, which, even if taken with many grains of allowance, exhibits a remarkable degree of intelligence that, in many respects, seems scarcely less than human: "Peter" belonged to an officer in the British Army, and was a large and powerful specimen of his class. He was a general favorite, his unusual sagacity and varied accomplishments forming a source of endless amusement, and, although somewhat mischievous, his gentleness of disposition and genuine love of fun readily secured forgiveness for occasional annoying pranks. Unfortunately, however, Peter had an enemy in the person of a diminutive and unpopular subaltern, to whom he appears, in some mysterious way, to have rendered himself particularly obnoxious. During a temporary absence of his master the monkey was intrusted to the care of a brother officer, who, being anxious that he should suffer no harm, chained him to a chest of drawers in his own room. This well-meant restraint did not coincide with Peter's desire for freedom, and, left to his own resources, he sought about for some means of diversion. Having first forced open the locks of all the drawers, he strewed their contents upon the floor, and seated himself in the midst, "monarch of all he surveyed." Next, discovering an inkstand within reach, he bedaubed with its contents every article belonging to his hospitable entertainer. When his host returned, Peter appeared totally unconscious of having been guilty of the slightest misdemeanor. He was not punished, but summarily dismissed from his comfortable quarters and allowed to wander freely about the barracks. All went well for a time, but, later in the course of one of his rambles, Peter unluckily encountered his enemy, and, springing upon the shoulder of the irate and alarmed subaltern in the presence of a large number of officers and men, he nearly succeeded in drawing the sword of his victim, who, according to report, was not at all likely to draw it himself. The ludicrous position of the latter, amid the loud laughter of the men, served only to increase the subaltern's hatred of the popular monkey. Shortly after this, Peter was fired at and seriously injured. Though it was impossible to prove who was guilty of this cowardly act, it was naturally attributed to the subaltern, who, it was well known, had never forgiven the indignity inflicted upon him in public. Peter's friends exerted themselves to save his life; the slugs were extracted, and he was soon convalescent. At this juncture his master returned, and the joy of the monkey was unbounded. "He clung to him and fondly embraced him over and over again, repeatedly kissing or rather licking his face and hands, with every possible demonstration of the most devoted attachment." When the first paroxysm of delight was over, Peter clasped the arm of his friend to bespeak special attention, "pointed with his own forefinger to each of the wounds whence the slugs had been taken, trying at the same time, in the nearest approach to speech that he could accomplish, to tell the piteous story of his narrow escape from a violent death. . . . It is questionable if the most intellectual of human beings not gifted with the power of speech could have acted more pathetically, or indicated more vividly what had occurred to them during the absence of their natural protector and dearest friend."

Announcement of Astronomical Discoveries.—For the purpose of mailing astronomical discoveries known to the public, speedily and in a systematic manner. Lord Lindsay has devised a plan for international communication of such information, and sent circulars to the leading observatories, public and private, everywhere. Ho promises to distribute notices of discovery within twenty-four hours of the receipt of the telegram to those who favor him with their addresses. The following is the substance of his circular:

The Observatory, Dun Echt, Aberdeen,
November 1, 1879

Sir: I am very anxious to form some system whereby information of astronomical interest may be rapidly and widely disseminated among English observers, and I would beg to ask for your assistance in carrying out my plan. In the event of your discovering a comet, new star, or other object of immediate interest, I would ask you to send me a telegram announcing the discovery, and giving such details as are usual. I have purposely omitted to mention minor planet discoveries, inasmuch as this branch is already admirably carried out by the Berlin Observatory. For convenience, the telegram should be in the form recommended by the Vienna Academy in the seventy-fifth volume of the "Astronomische Nachrichten," No. 1785, page 142, as follows: Comet (new star, etc.), discoverer, date, local mean time of observation (in hours and minutes), place of discovery, right ascension in arc (degrees and minutes), north polar distance (degrees and minutes), daily motion in R. A. and N. P. D. (minutes of arc), plus or minus, description, diameter of comet, etc. (in minutes of arc).

Thus a telegram would run:

Comet Winnecke, 5 April, 1445. Strasburg, 3315707508. Motion 0, minus 60.

This would read:

Comet discovered by Winnecke, 5th of April, 14 hours 45 minutes mean time, Strasburg, R. A., 331° 57', N. P. D., 75° 8'. Daily motion, stationary, R. A, minus 60' in polar distance.

Naughts should be put in where there are no significant figures, so as to make three figures for degrees and two for minutes (five in all), in R. A. and m N. P. D.; similarly, four in the local time.

Telegrams, etc., should be addressed Observatory, Dun Echt, Aberdeen.

(Signed)Lindsay,

President Royal Astronomical Society.

Arsenic in the Household and School.—When somebody is accused of having dosed a fellow mortal to death with arsenic. State authority and newspaper interest immediately vie with each other in their efforts for the protection of human life. Unfortunately, however, both are much less alive to other and far greater dangers arising from the reckless employment in the arts and manufactures, and the ignorant introduction into our households, of this same deadly poison. Its use in the preparation of pigments is very common, and the employment of these for coloring articles of attire and for the various styles of paperhangings is scarcely less so. Not only are those engaged in the manufacture of these coloring matters exposed to the deleterious influence of the poison, but far larger numbers ignorantly purchase and use the articles containing it, and in a way that makes its action but little less virulent than the direct administration of the pure drug. Instances of this are constantly recurring in medical practice. Socks colored with compounds containing arsenic have produced disease of the feet; boots lined with flannel colored with Scheele's green have caused the death of their wearers; bright maroon-colored flannel worn next the skin, paper collars, neckties, hat-linings, gloves, artificial flowers, and even ladies' dresses, have all been the cause of disease from the presence of this poison. Its use for coloring wall-papers, and especially the cheaper sorts, is almost universal; and, while the greens are probably the worst of the lot, they are by no means the only ones containing arsenical pigments. A recent number of the "Lancet" gives an account of an aggravated case of poisoning, due to a red paper on the walls of a sitting room; and arsenic has also been found in white, gray, blue, mauve, and brown wallpapers in abundance. As an instance of the utter disregard of consequences shown by manufacturers in the use of these pigments, we may cite the statement published by Miss Osborne, of the Sydney Hospital, New South Wales, that large quantities of poisonous pigments are consumed in that colony in coloring sweetmeats for children. We give in another place in this number a letter from a chemist in Pittsburg, showing an equally flagrant case of carelessness in the manufacture and use of arsenical papers for the operations of the kindergarten. People who thus disregard the welfare of their fellows, scattering poison broadcast in a way that neither age nor condition can escape, are, we submit, entitled to some small share of attention from the press, and from the courts.

Artificial Diamonds.—The "todo" about the artificial production of the diamond has been set at rest by Professor Maskelyne, who, in reply to numerous letters of inquiry on the subject, sends to "Nature" the results of his examination of the Macteor specimens which came into his hands for the purpose. He tested these so-called diamonds—1. With reference to their hardness; 2. Their refracting power; and, 3. Their combustibility. The samples sent to him were "too light to possess appreciable weight, too small even to see, unless by very good eyesight or with a lens," yet were sufficiently large to serve his purpose. "A few grains of the dust—for such the substance must be termed—were placed between a plate of topaz—a cleavage-face with its fine, natural polish—and a polished surface of sapphire, and the two surfaces were carefully 'worked' over each other with a view to the production of lines of abrasion from the particles between them. There was no abrasion. Ultimately the particles became bruised into a powder, but without scratching even the topaz. They were not diamond. Secondly, some particles more crystalline in appearance than the rest were mounted on a glass microscope slide and examined in the microscope with polarized light." They each and all presented powerfully the property of doubly refracting light. Finally, two of these microscopic particles were exposed to the intense heat of a table blowpipe on a bit of platinum-foil. They did not burn. They were afterward placed in contact with two little particles of diamond-dust, exceeding them in size, and the experiment, on being repeated, "showed that the diamond particles glowed and disappeared, while the little particles from Glasgow were as obstinate and as unacted on as before." When subjected to a stream of oxygen gas the result was the same. Hence, Professor Maskelyne concludes that the substance supposed to be artificially formed diamond is not diamond and is not carbon. Further experiments led him to the conclusion that it consisted of some crystallized silicate, or possibly of more than one such.

The fate of the Glasgow diamonds has induced Professor W. Mattieu Williams to send to "Nature" an account of his experience in diamond-making, for the benefit of those who may have an attack of the diamond mania. He states that for the popular class-room experiment of burning phosphorus in oxygen he used a cup of chalk, deeper and with a smaller rim than the brass cups usually made for this purpose—the object of this being to check too rapid outburst of combustion. He observed that a cup, several times used for this purpose, became coated on the inside with a hard, glassy enamel, which he supposed to be phosphate of lime. To test this, the cup was thrown into hydrochloric acid and dissolved, but at the bottom there remained a residue of insoluble crystalline particles. "Could it be possible that the carbonic acid, driven off by heating the chalk, had, in reaching the heated phosphorus, become dissociated, its oxygen combining with the phosphorus, and its carbon thrown down as veritable diamond?" These crystalline particles when tested were found to scratch a glass pestle and mortar in which they were rubbed, but were too small for further examination. To obtain a better supply, phosphorus was dissolved in bisulphide of carbon, and this solution mixed with pounded chalk constituted a paste which was put into a porcelain crucible, and the mass fired by heating it over a Bunsen burner. "It blazed magnificently, throwing out eruptive jets of flame. Here, in the absence of surrounding oxygen, the carbonic acid had every opportunity of becoming dissociated or reduced by the heated phosphorus." The residue, treated with hydrochloric acid, yielded a quantity of crystalline grains. These, when tested, left scratches on the glass mortar and pestle, and even seemed to leave slight marks upon an agate pestle and mortar. Examined, however, under a microscope, they resembled pebbles more nearly than crystals, and this fact led to the theory that they were "miniature chalk-flints formed by the fusion and aggregation of the silicious cuticles of fossil diatoms." This was tested by precipitating pure carbonate of lime, soaking it with the phosphorus solution, and, after firing it, treating it with hydrochloric acid, when all trace of dissociated carbonic acid disappeared, and neither diamonds nor other crystalline residue remained.

A New Preservative Process.—Herr Wickerscheimer, preparator in the Zoötomlcal Museum of Berlin, has invented a process for preserving plants and the bodies of animals, which has appeared to be of such value that the Prussian Government has procured the patent, and given it to the public. The inventor describes the process in his specifications as follows: "I prepare a fluid with which I impregnate the object to be preserved in different ways, according to its nature or the purpose I have in view, or the manner in which I preserve it. The bodies of men and animals preserved by this process retain perfectly their form, color, and suppleness, so that we may take sections from them years afterward for the purposes of science or of criminal justice. Under its operation, corruption and the insalubrious odors produced thereby cease. The muscular tissue presents on cutting it a condition like that of a fresh body. Finished preparations of selected parts, as the ligaments, lungs, intestines, etc., preserve their softness and flexibility, and the hollow parts may be even blown out. The parts of bugs, crustaceans, and worms, remain movable without exception. The colors may be made to remain perfect if it is desired, in animal as well as in vegetable bodies. The preserving fluid is prepared as follows: In 3,000 grammes (46,500 grains) of boiling water dissolve 100 grammes (1,550 grains) of alum, 25 grammes (387 grains) of common salt, 12 grammes (186 grains of saltpeter, 60 grammes (930 grains) of potash, and 10 grammes (155 grains) of arsenious acid. To ten quarts of the neutral colorless and odorless fluid add four quarts of glycerine and one quart of metylalcohol. The process of preservation, which is applicable to the dead bodies of men, dead animals, and vegetables, as well as to single parts of the same, consists, to speak generally, in soaking them and impregnating them with this mixture. If the preparations are to be preserved dry, they are kept in the fluid for from six to twelve days, according to their size, then taken out and dried in the air. The ligaments of skeletons, the muscles, crustaceans, bugs, etc., will then remain soft and pliable, so that all the natural movements can be produced on them at any time. Hollow organs, as the lungs, intestines, etc., are filled with the fluid before being put into it. After taking them out and pouring out the fluid from the inside, they are dried, and should then be blown out. If it is desired to preserve smaller animals, like lizards and frogs, and vegetables, with their colors unchanged, they should not be dried, but should be kept in the fluid. If bodies of men or beasts are to lie for a considerable time before being used for scientific purposes, it is enough to infect them with the preservative fluid. For this purpose, I apply, according to the size of the object, one and a half litre (about three pints) of the fluid for a child of two years, five litres (or quarts) for a grown person. The muscles will appear then, even after the lapse of years, fresh when cut. If the infected bodies are kept in the air, they will lose their fresh appearance, and the epidermis will become somewhat brown; but that may be avoided if the body is rubbed on the outside with the fluid, and is then kept shut up in an air-tight case. The last method is recommended in the case of corpses which are to be kept for some time before they are buried; instead of having the usual stiff look, the features and color will seem fresh and unchanged, and the bodies will not have a trace of odor. For embalming, I infect the corpse first, then put it into the fluid, and, after keeping it there for a few days, rub it and dry it, wrap it up in a cloth moistened with the preserving fluid, and keep it in an air-tight case. The treatment in different cases is governed by circumstances, but the composition of the preserving fluid is always the same."

Applications for Phylloxera.—M. Mouillefert, of the École Rationale d'Agriculture of Grignon, reported to the Academy of Sciences, Paris, November 10th, the results which had been obtained from the treatment of vines affected by the phylloxera with sulpho-carbonate of potassa. The efficacy of the salt appeared to be certain when it was applied with water according to the rules approved by the commission of the Academy. Vines that were very much weakened had been regenerated after such treatment, became free from spots, and bore fruit as they had done before they were attacked. The importance of water as the vehicle with which the remedy should be applied was strongly insisted upon. The sulpho-carbonate may be applied in all weathers and in all seasons, even in the cold months, without any danger to the vines; up to a certain dose (eighteen to twenty-five ounces to the square yard), the remedial effects are in nearly a direct proportion to the amount of the salt applied. At a subsequent meeting of the same body, December 1st, M. Frémy disputed the value of the sulphuret of carbon as a remedy for the phylloxera, and asked several questions of M. Thénard, who has recommended the application of that substance, as follows; 1. We know that sulphuret of carbon kills the phylloxera, but it also kills the vines; can we find a certain way of securing the former result while we avoid the latter? 2. Can sulphuret of carbon be easily and practically applied without affecting the health of the vine-dressers? 3. It is alleged that, by sacrificing one third of the vines, we can save the other two thirds; is this true? 4. Has the invasion of the phylloxera been arrested anywhere by the employment of sulphuret of carbon? Even if we are pointed to an apparent instance of the fact, we shall have to accept it with reserve; for cases are known in which vines which have not been treated still remain healthy in the midst of contaminated vineyards. M. Thénard failed to give a precise reply to the questions, which indicate very clearly the qualities that are required in a safe and efficacious remedy for the disease.

Parkes on Tobacco-Smoking.—We give below a very interesting and instructive letter written by the late Dr. Parkes, a short time before his death, in reply to a request for his views on the subject of tobacco smoking, and recently published in the "Lancet":

My dear Dr. Pratt: I think my state of mind as regards tobacco is very much what yours seems to be. I have honestly tried to collect evidence from moderate smokers, both medical men and others, and, when tolerance has been established, I have never been able to make out any symptoms which implied injury. In the case of many medical men whom I have asked to study their own condition, the answer has always been the same—viz., they could see no harm or disturbance of any function. Even in some cases of enormous smokers—i. e., men who rarely were without a pipe or cigar—I could learn of no injury. On the other hand, I have seen, like all of us, men complaining of dyspepsia, nervousness, palpitation, etc., and who were much better for leaving off smoking; in fact, in these cases there could be no doubt of an injurious effect. In boys of fourteen or fifteen who begin to smoke, I think I have observed that tolerance is slowly attained, that appetite is less, and I presume digestion and nutrition less good, and that the complexion becomes pasty and less florid and clear. There was a striking case of this kind in the son of a medical friend, who watched his son naturally very carefully, and who told me that the effect of the tobacco (a good deal was smoked) was quite unmistakable. I persuaded the son to lessen his tobacco one half, and his health certainly improved, but he was then a young man. That some injury, therefore, is sometimes produced, and especially on young people, seems to me quite clear; but it is curious, in other cases, how difficult it is to find ill effects, even in the young, when the quantity is not excessive. As to the effect on the young even, it is curious in Burmah to see children smoking in their mothers' arms; and yet when I was serving in Burmah, many years ago, I often saw a woman walking along smoking her cigar of tobacco rolled up in a plantain-leaf, and carrying on her hip her child of two or three years old, who also had his or her little cigar, which was smoked with the greatest gravity. On talking to the Burmese (who smoke constantly), they would never allow that even young children were in the least damaged. When I was in Turkey I tried to make inquiries of some of the intelligent Turkish gentlemen; one or two of them said that they thought the Turks had learned to smoke from the Europeans, and had been growing apathetic and dull ever since. But others laughed at this, and the rural Turk, who smokes a good deal, is a fine, active, energetic fellow. I have talked to many Germans, who all stand out manfully for tobacco. In conclusion, I confess myself quite uncertain. I can find nothing like good evidence in books; too often a foregone conclusion, without any evidence to back it, is given. I think we must decidedly admit injury from excess; from moderate use I can see no harm, except it may be in youth. My opinions are, you will see, very indefinite, and I would gladly see some really good evidence collected. If at any time you can send me any facts, I shall be very grateful.

Believe me, very sincerely yours,
E. A. Parkes.
Bitterne, Southampton, January 23, 1876.

Intoxicating Properties of the Hemp-Plant.—Mohammedans, Hindoos, and others, whose religion forbids them the use of alcohol, find in this plant a substitute which, though not so pleasant to the taste, is on the whole far less injurious in its habitual use. It is taken in various ways. Mixed with tobacco, it is smoked in the hookah, and, to those unaccustomed to it, smells abominably. It is also taken in decoction, and in a solid form in sweetmeats. In ordinary doses it acts as a gentle and pleasant stimulant, exciting none of the brutal coarseness produced by alcoholic excess. In larger quantities it appears to banish all sense of fear, and is often taken by the Indian sepoy before entering into action; and Mohammedan fanatics brave death under its influence. On account of this property, the Afghans are reported to have used it freely in their recent war with the English, many of the fierce onslaughts made by small parties of natives on the foreign soldiery being traceable to its effects. When taken in excessive quantities it produces a form of madness, characterized by a reckless passion to destroy every living thing that comes in the maniac's way. It is related of an English officer at Delhi that, desiring to try the effects of hemp on himself, he inadvertently took an overdose, and bareheaded, on a scorching day in May, rushed down the road, armed with a large knife, and fiercely attacked a bullock, which was the first thing he met. He was quickly secured and disarmed, and, under the care of the doctor, who shaved his head and applied ice, was soon brought to his senses again.

Common Sense in Emergencies.—The story is told of Brunei, the eminent engineer and builder of the Thames Tunnel, that one day, while amusing a child with tricks of sleight-of-hand, he attempted one which resulted in a serious accident to himself, and at the same time illustrated the danger of playing pranks with the mouth. The trick consisted in adroitly concealing a half sovereign in his mouth and pretending to bring it out at his ear. All at once to his dismay the coin slipped down into his gullet, and there stuck in spite of every effort, surgical or otherwise, to dislodge it. In this dilemma common sense came to the rescue. Brunei himself devised an apparatus to which he was strapped head downward, keeping his mouth open, when, to his inexpressible relief, the coin dropped from its dangerous position and rolled out upon the floor. A sword-swallower, who once lost a bayonet in his throat during one of his public performances, resorted to similar means for recovering it, and was equally successful.

Passivity of Iron.—It has been observed that iron which has been treated with concentrated nitric acid assumes a passive state and refuses to be acted upon by the common or diluted acid, but the cause of the property has not hitherto been satisfactorily explained. M. Louis Varenne reported recently to the French Academy of Sciences that he had remarked that passivity was destroyed and the metal could be made to yield to the solvent action after a shock or jar was given to it, or a current of carbonic acid or hydrogen gas was passed over it. He was led to believe that an envelope of gas was formed around the metal which protected it, and, on examining some passive iron, found that it was actually covered with a layer of gas. The metal was then placed in a receiver and a vacuum was produced, with care not to touch the iron or disturb it in any way, after which it was plunged into the diluted acid, when it was readily attacked. The nature of the protecting gas was ascertained by introducing a little air into the exhausted receiver, when the orange color characteristic of the nitrous vapors was observed. The gaseous sheath is, therefore, chiefly composed of the deutoxide of nitrogen.