Popular Science Monthly/Volume 3/June 1873/Miscellany
MISCELLANY.
Action of Drought and Cold on Forest-Trees.—In an able paper on the manner in which the distribution of plants and animals may be influenced by extraordinary changes in the character of the seasons, published in the American Naturalist for November last, Prof. N. S. Shaler attributes the wide-spread destruction of evergreen trees, which became so painfully apparent during the previous spring, to the action of drought and cold. The year preceding was, in New England, one of the dryest on record, the ground, when winter set in, holding a comparatively small amount of moisture. This left the roots of trees deficient in sap. Not being well protected by snow, the ground in winter was frozen to a great depth, and, as the frost left the roots in spring, they remained for some time in contact with relatively dry earth, thus causing a shock too great for their vitality to withstand. During the succeeding summer Prof. Shaler also observed a remarkable scarcity of snakes and toads, which he is likewise inclined to ascribe to the great severity of the previous winter. Concerning the effect of such climatic accidents on the character of our forests, he says:
"Small as the destruction of forest-trees is, it will doubtless add several per cent, to the deciduous trees of New England, and remove an equal amount of conifers. The conifers seem to be relics of an old time, and not competent to wage a successful war with their younger and more elastic competitors, the oaks, beeches, and other deciduous trees. Every gap that is made in our forests of cone-bearing species is filled not with their legitimate successors, but by forms from the other class of trees. Let us suppose that the shock of the last season had been great enough to kill off the whole of our pines, the result would have been a complete change in the character of our forests; oaks generally would take the vacant place. This would affect the character of the undergrowth very materially, for the lesser plants of a pine-wood are very different from those which flourish beneath oaks. This would have had a very great effect upon insect-life, and more or less directly influenced the number and character of the birds and the mammals. Even the climate would be in some small measure influenced, for a pine-forest retains the snow better than one which loses its leaves in the winter, and thus tends to secure a more equable temperature in the region where it lies. Thus we see that an accidental drought might bring about a change in the assemblage of vital conditions on the surface of the land, as great as those which, when recorded in strata, we accept as indicating distinct geological formations."
Dental Art among the Japanese.—Dr. W. St. George Elliott, formerly of this city, now at Yokohama, Japan, sends to the Dental Cosmos an interesting account of Japanese habits in regard to teeth, and of the state of dentistry in that empire. He says that the teeth of the daughters of Japan are objects of envy, and it is remarkable that a nation who place so much value upon their teeth should keep up the custom of blacking them after marriage. As a race the Japanese have not good teeth, and it is rare to find an old person with any at all. Their tooth-brushes consist of tough wood, pounded at one end to loosen the fibres. They resemble paint-brushes, and owing to their shape it is impossible to get one behind the teeth. As might be expected, there is an accumulation of tartar which frequently draws the teeth of old people. The greatest accumulation is behind the lower orals, and these are frequently cemented together by a dense, dark-brown deposit, a quarter of an inch in thickness. Their process of manufacturing false teeth is very crude. The plates are made of wood, and the teeth consist of tacks driven up from the under side. A piece of wax is heated, and pressed into the shape of the roof of the mouth. It is then taken out and hardened by putting it into cold water. Another piece of heated wax is applied to the impression, and, after being pressed into shape, is hardened. A piece of wood is then roughly cut into the desired form, and the model, having been smeared with red paint, is applied to it. Where they touch each other a mark is left by the paint. This is cut away until they touch evenly all over. Shark's-teeth, bits of ivory, or stone, for teeth, are set into the wood and retained in position by being strung on a thread which is secured at each end by a peg driven into the hole where the thread makes its exit from the base. Iron or copper tacks are driven into the ridge to serve for masticating purposes, the unequal wear of the wood and metal keeping up the desired roughness. Their full sets answer admirably for the mastication of food, but, as they do not improve the looks, they are worn but little for ornament. The ordinary service of a set of teeth is about five years, but they frequently last much longer. All full upper sets are retained by atmospheric pressure. This principle is coeval with the art. In Japan, dentistry exists only as a mechanical trade, and the status of those who practice it is not very high. It is, in fact, graded with the carpenters—their word hadyikfsan meaning tooth-carpenter.
Vegetable Ivory.—The kernel of the corrozzo-nut so closely resembles ivory as to merit the title of vegetable ivory. The plant (Phytclephas macrocarpa) which produces this nut belongs to the palm-tribe. It grows in South America, and possesses extraordinary beauty. The stem is short, and lies along the ground, but from its crown issues a sheaf of light-green, pinnated leaves, like ostrich-plumes, which often attain a height of 30 or 40 feet. The fruit of the plant is as large as a man's head, and contains a number of nuts of rough, triangular shape, each being almost as large as a hen's egg. When fully ripe, the kernel of the nut is very hard and white, and hence the name phytelephas (vegetable ivory). This is now largely used as a substitute for elephant ivory, in the manufacture of buttons and various ornaments, and might easily pass for the animal product. Indeed, the best judges are often deceived by the close resemblance between the two. Advantage is taken of this circumstance in Germany by dealers in bone-dust to adulterate their wares with the waste of the factories where the vegetable ivory is manufactured. The best mode of detecting the adulteration is to burn the suspected article. If it contains any considerable amount of the vegetable substance, the application of heat will cause it to give out an odor much like that of roasting coffee; but, if it is pure bone-dust, or nearly so, it will emit a nauseous and very disagreeable stench.
Coloring Matter in Blood.—A writer in Virchow's Archiv finds in blood two distinct coloring-matters. One of these is readily soluble in water and alcohol, but not so readily in ether. When dry it has a dark, greenish-brown color, and is carbonized on the application of heat, without ebullition. The ash is strongly colored with iron, and contains phosphoric and silicic acids, and a trace of alkali. It does not yield hemin-crystals under any treatment. With guaiacum-tincture and turpentine-oil it gives the well-known blue color, and under the spectroscope is found to possess the characters attributed to alkaline oxyhematin by Preyer. It appears to be identical with Von Wittich's hematin. The other coloring-matter consists of dark, blue-black microscopic crystals, insoluble in water, alcohol, ether, chloroform, and acids, but soluble in weak alkaline solutions, to which they give a brownish tint. If it be then precipitated by acetic acid, and dried, it will, on being treated with sal-ammoniac and glacial acetic acid, yield beautiful hemin-crystals. When reduced to an ash, it consists of pure oxide of iron. It seems to be identical with Virchow's hematoidin.
Elimination of Carbonic Acid by the Skin.—The amount of carbonic acid given out of the system through the skin in man has been variously estimated by physiologists; but, as their methods of determination were all more or less defective, it is not surprising that their results should differ very considerably from one another. Thus Reinhard's estimate makes the average daily elimination of carbonic acid through the skin about 35 grains, while Gerlach makes it 120 grains; other authorities ranging all along between these two extremes. A special apparatus has been devised by Dr. Aubert, of Rostock, for more accurately ascertaining the amount of this excretion. He seats a person within a box, which fits lightly around the neck, and through which a gentle current of air is passed. Dr. Aubert, in this way, finds that in the course of 24 hours a maximum of 97 and a minimum of 35½ grains of carbonic acid are eliminated by the skin of the whole body, exclusive of the head. Variations of temperature will of course affect the amount of carbonic acid thus excreted. In the experiment, the external temperature was about 86° Fahr.
Remarkable Diamonds.—A diamond waa recently discovered, at the Cape of Good Hope, which weighs 288 carats. This the Builder calls enormous, and accordingly christens the new stone "Queen of Diamonds." But the Builder is plainly in error here, for there are many diamonds which weigh far more. Thus, the Grand Mogul is the owner of a rose-diamond which, in the rough state, weighed 780½ carats. It lost very largely in the cutting, weighing now only 136 carats. It is valued at over two and a quarter millions of dollars. A potentate in Borneo owns a diamond weighing 367? carats. The "Regent" weighed in the rough 410 carats. The "Orloff" weighs 1943⁄4, and may have weighed thrice as much in the rough state. An Austrian diamond weighs 139½, and, as the lapidary cannot cut these stones without depriving them of at least half their weight, it must have been, in the rough, larger than the Cape "Queen." But the name given to this newly-found stone will appear still more incongruous when we consider its quality. A diamond is said to be of the first water when it is perfectly limpid and colorless, and free from flaws, and of the second or third water in proportion as it departs from this standard. But this Cape diamond is of a yellow color, and marked with flaws—it is, therefore, not of the first water, and would in all probability be classed by the lapidary as of the third water.
Production of Sea-Salt in Portugal.—The salines of Portugal, at Setubal, Lisbon, Aveiro, and Algarve, yield annually 250,000 tons of sea-salt. According to Prof. Wauklyn, in the Mechanics' Magazine, the process of manufacture at the first-named place is as follows: There is a vast reservoir of about four acres in extent, eight inches deep, and partitioned into squares of about 130 yards in surface. Roads, three feet wide, separate the squares, and the latter all communicate with the main reservoir of seawater. In autumn the whole salt marsh is overflowed to the depth of 20 inches. This water evaporates in the spring, the roads appearing above the surface in June. Then the tanks are cleaned out, and afterward left to themselves, and recharged from time to time with new supplies of water. In 20 days a layer of salt over one inch thick is found. This, the first crop, is collected, and the tanks filled again. In 20 days another crop is gathered. If the season is favorable, three crops may thus be collected before September, when the marsh is flooded for the winter.
Controlling Sex in Butterflies.—The American Naturalist for March contains an admirable essay by Mrs. Mary Treat, in which she brings a long array of facts to prove that the sex of butterflies depends, in some cases at least, rather upon the external conditions surrounding the larva, or caterpillar, than on its anatomical structure. The results of the author's experiments contradict the doctrine of most entomologists, which asserts that even in the eggs of the Lepidoptera the germs of sexual difference may be discerned. The editor of the Naturalist quotes from several authorities, to show that, in the case of all animals which reproduce by eggs, the sex is probably determined at or about the time of conception, or at least early in the embryonic stage. Mr. T. W. Wonfor also, writing on "Certain Wingless Insects," in Hardwicke for March, asserts that the very same conditions, viz., lack of abundant food, or alternations of scanty and bountiful food, which, according to Mrs. Treat's experiments, determine the sex of the future imago, or butterfly, tend only to "produce dwarfs or monstrosities." The writer in Hardwicke, we may add, holds that no sex-difference is discernible either in the eggs or in the larvæ. Mrs. Treat's observations and experiments, it will be seen, were very thoroughgoing and very carefully conducted, and will, doubtless, attract the earnest attention of naturalists. Some two years ago Mrs. Treat placed a larva, which had already taken some steps toward the chrysalis state, upon a fresh stem of caraway, and was surprised to see it commence eating. It then continued to eat for some days before changing to a chrysalis. She next placed a number of other larvae on similar stems of caraway, while still others she deprived of food altogether. Those of the last lot which completed their transformations were all males, and all the butterflies from the first lot were females.
The next experiment was commenced in June last. In July the author had about two hundred larvæ feeding at once. Immediately after the last moult, a number of these were shut up in paper boxes, five to ten in a box, and deprived of food. If, two or three days after confinement in the boxes, any of the larvae were found wandering about, they were fed very sparingly. Nearly all of them lived to complete their transformations. Another lot were, in like manner, put in boxes, but supplied with abundant food. From the latter came sixty-eight females and only four males; from the former seventy-six males and only three females. Five larvæ that were eating vigorously were also taken from their food a day or two before they would have been sated. Of these, four turned out females.
Another experiment was this: Soon after the last moult, twenty larvae were deprived of food for twenty-four hours. Then ten of them were given abundant food again, as long as they would eat. One of these met its death by accident in the chrysalis state, but all the rest became female butterflies. Of the other ten, two died in the chrysalis state; the remainder were males.
Again: Some twenty half-grown larvae of the Vanessa antiopa were accidentally deprived of food. Twelve of them died of starvation, but the remainder completed their transformations. On dissection, these eight all proved to be males. The indefatigable student pushed her investigations further still, for, having found thirty-three larvae of an unfamiliar species, she fed them abundantly, till they would eat no more. The rare and beautiful moth Dryocampa rubicunda made its appearance in due time, and there were twenty-nine females and only two males, the remaining two having either escaped or died. Finally, a lot of the same species of caterpillars were left without food. Some of them were killed by a parasite, others died of starvation, and the seven which survived were all males.
Hydrophobia and the Imagination.—The period of time which elapses between the bite of a rabid animal and the appearance of hydrophobic symptoms varies over a very wide range indeed. The disorder seldom makes its appearance earlier than the eighth clay after inoculation (if inoculation there be); or, again, the virus may be hidden in the wound for weeks, months, or even years. Physicians say that, in most cases, hydrophobia manifests itself in from four to eight weeks after the bite, though there are many authentic cases where the period of incubation extended over eight or nine months, and in one instance even as long as seven years. In this term incubation is implied an hypothesis gratuitously assumed, and scarcely susceptible of direct demonstration. It is found that a patient bitten by a rabid animal passes a certain length of time without manifesting hydrophobic symptoms, and it is supposed that the germs of the disease have been slowly maturing. But, as there is no other disease whose period of incubation is so long or so varying in duration, the hypothesis which traces hydrophobia to animal virus finds no foundation in analogy, and is consequently very weak.
It is, therefore, very natural that medical men should begin to study the whole question anew, and attempt other explanations of this disease. Thus, Dr. D. H. Tuke, whose paper on the "Blanching of the Hair" appeared in our December number, has lately published a work on the "Influence of the Mind upon the Body," and there supports the proposition that hydrophobia is produced solely by the action of the imagination. The author cites cases where, beyond all doubt, hydrophobic symptoms were developed without inoculation. A notable instance is that of a physician of Lyons, named Chomel, who, having aided in the dissection of several victims of the disorder, imagined that he had been inoculated with the virus. On attempting to drink, he was seized with spasm of the pharynx, and in this condition roamed about the streets for three days. At length his friends succeeded in convincing him of the groundlessness of his apprehensions, and he at once recovered. Rush also tells of cases of spontaneous hydrophobia, which arose from no other cause but fear and association of ideas.
A German physician, too, Dr. Marx, of Gottingen, as we learn from the Clinic, is disposed to take this view of hydrophobia, and to regard it as a psychical affection, the result of morbid excitement of the imagination. He is of the opinion that the bite of a mad dog does not, of itself, produce the symptoms of hydrophobia, and that, were it not for the common belief in canine virus, the spasms and other manifestations of the disease would not supervene. This view is confirmed by the fact that young children, who are not acquainted with the common belief as to hydrophobia, may be bitten by mad dogs and escape spasms and madness. He adds:
"If we are able, as in olden times, and in the case of children, to instruct or induce men to be perfectly quiet after they are bitten by a rabid dog, not to tremble or be frightened, but to banish anxiety, to control their imagination, and, with patience and hope, to look forward to recovery, and also to persuade the well to remain with the unfortunate one, and not to run away, but to cheer him in the hour of trial, then the means may have been discovered by which the effects of the accident are to be banished, and the poison in the wound neutralized."
Odorous and Liquifiable Gases: what Gases may be liquefied.—A writer in the Pharmaceutical Journal notes a remarkable relation between the odor of gases and their reducibility to the liquid or solid state. Thus oxygen, hydrogen, and nitrogen, which have no odor, cannot be reduced either by pressure or by cold. On the other hand, chlorine, which has a very strong odor, is easily condensed to a liquid. Again, the protoxide of carbon, being odorless, cannot be condensed, while the dioxide or carbonic acid, which has a faint, pleasant, and pungent odor, can be reduced to a liquid, and even to a solid state. Nitrous and nitric oxide, the latter of which is odorless, show similar phenomena. An exception to the general rule, that gases which are odorous are condensible, is furnished by acetylene, which, though having a faint garlic smell, has never been condensed. Usually condensability stands in a direct ratio to the strength of the odor possessed by a gas. Thus, sulphurous acid, which has a most intense odor, becomes a liquid under a pressure of two atmospheres, at 15° Fahr., while nitrous oxide, which has but a faint smell, requires fifty atmospheres, and a temperature of 7.2° F. A few gases having a fetid odor are exceptions to this law, but it holds good so generally, that a list of gases, arranged according to their reducibility, and another list arranged according to their properties of smell, will show a rough though marked coincidence.
The Spectroscope and the Bessemer Process.—Prof. Tidy, in a lecture on the spectroscope, thus briefly describes its important practical application in the Bessemer process: "Cast-iron contains a great amount of carbon, and in the Bessemer process this carbon is got rid of by burning it out of the molten iron with a blast of atmospheric air. The fluid cast-iron is placed in a large retort lined with refractory clay. This retort, the converter as it is called, turns on a pivot. Through the pivot a tube passes in connection with a very powerful blowing apparatus, by which air can be blown into the molten iron. That air burns out the carbon, the heated gases issuing as a flame from the converter. Now, it is very important to stop that blowing process directly the time arrives. Ten seconds too soon, or ten seconds too late, and the charge is spoilt. Experience, I grant you, does guide the worker, but experience is a costly thing; and this I am confident of: laud experience as you will, it will not weigh down the scale when we have in the opposite pan exact scientific experiment. The Bessemer flame, as it issues from the converter, is examined by the aid of the spectroscope. Numerous substances are visible—sodium, potassium, iron, hydrogen, carbon, etc. All of a sudden, in a second, the carbon-lines disappear, and that is the moment when the air-blast must be turned off, for now the carbon is burnt away, and the iron is converted."
New Material for Illuminating Gas.—Le Gaz, the gas-light journal of Paris, calls the attention of the directors of gas-works to a new illuminating material, vegetable pitch. This material is made by the Patent Oil and Stearine Company, of England, from the residues of the manufacture of olive, palm, cocoa, and other oils. In England it is widely used, being employed in gas-works in connection with coal, with a view to augment the volume of gas, as well as its illuminating power. The London Gas-light Company constantly employs it, mixing it in certain proportions with the coal, and the Gas Company of the Crystal Palace uses this material only, to produce a rich gas. The pitch is solid and glistening, and distills very rapidly in the common gas-retorts, leaving scarcely any residue. In case a large amount of gas is required to be furnished in a very short time, this property of rapid distillation is of high importance. Its yield of gas is said to be very considerable, being 765 to 850 cubic metres (830 to 930 cubic yards) to the ton. The illuminating power of this gas is equal to that of 33 sperm-candles, 5 to the pound. It is too rich to be used with the ordinary burner. It is best employed to enrich gas made from inferior coals. It contains scarcely any sulphur0.87 per cent. The analysis of the pitch is as follows: Volatile matter, 74.40; fixed carbon, 21.72; ashes, 3.88.
Antiquity of Man.—The following letter from Sir John Lubbock appeared in "Nature" for the 27th of March: "I have received a letter from Mr. Edmund Calvert, in which he informs me that his brother, Mr. Frank Calvert, has recently discovered, near the Dardanelles, what he regards as conclusive evidence of the existence of man during the Miocene period. Mr. Calvert had previously sent me some drawings of bones and shells from the strata in question, which Mr. Busk and Mr. Gwyn Jeffreys were good enough to examine for me. He has now met with a fragment of a bone, probably belonging either to the dinotherium or a mastodon, on the convex side of which is engraved a representation of a horned quadruped 'with arched neck, lozenge-shaped chest, long body, straight fore-legs, and broad feet.' There are also, he says, traces of seven or eight other figures, which, however, are nearly obliterated. He informs me that in the same stratum he has also found a flint flake, and several bones broken as if for the extraction of marrow. This discovery would not only prove the existence of man in Miocene times, but of men who had already made some progress, at least, in art. Mr. Calvert assures me that he feels no doubt whatever as to the geological age of the stratum from which these specimens are obtained. Of course I am not in a position myself to express any opinion on the subject, but I am sure that the statements of so competent an observer as Mr. Calvert will interest your readers."