Popular Science Monthly/Volume 7/July 1875/Miscellany

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Notices of Recent Earthquakes.—The American Journal of Science for May gives a summary of earthquakes for the year 1874, prepared by Prof. C. G. Rockwood, Jr., of Rutgers College, New Jersey. They are reported from nearly all quarters of the globe, forty-three in number. Two of these were disastrous, but in most cases the shocks appear to have been light.

Fourteen shocks are reported as having occurred in the United States. The most important of these took place in North Carolina, in Bald and Stone Mountains. The shocks continued at intervals from February 10th to April 17th, with explosive and rumbling noises. The most severe shock was felt February 22d. On one occasion the sound of the shock resembled that made by blasting in a deep quarry, first explosive, then reverberating.

The shock which occurred in the vicinity of New York City, December 10, 1874, is noticed. It extended as far as Peekskill on the north, and Norwalk, Connecticut, on the east. The shock was most severe in the neighborhood of Tarrytown and Nyack, but did no damage anywhere.

The most disastrous earthquakes occurred at and near Harpoot Mission, Eastern Turkey, destroying the houses of Haloosi, a considerable town near that place, and at Volcan del Fuego in Guatemala. This earthquake destroyed the town of Duenos. From a small mountain near the base of the Volcan del Fuego there issued an eruption of cold compact mud.

Testing Iron and Steel.—We have received the programme of organization of a Board appointed by the President, in accordance with the provisions of an act of Congress, making "appropriations for sundry civil expenses of the Government for the fiscal year ending June 30, 1876, and for other purposes."

The instructions of the Board are, to determine by actual tests the strength and value of all kinds of iron, steel, and other metals, which may be submitted to it, or by it procured, and to prepare tables which will exhibit the strength and value of said materials for constructive purposes. The members of this Board are Lieutenant-Colonel T. T. S. Laidley, U.S.A., President, Commander L. A. Beardslee, U.S.N., Lieutenant-Colonel Q. A. Gillmore, U.S.A., Chief-Engineer David Smith, U.S.N., W. Sooy Smith, C.E.. A. L. Holley, C.E., and R. H. Thurston, C.E., Secretary.

The Board has organized into standing committees to conduct special experiments and investigations, during the delay in preparing the testing machinery for the regular work of the Board, and afterward, as leisure will permit. These investigations are expected to be made with critical and scientific accuracy, and will consist in the minute analysis of a somewhat limited number of specimens, and the precise determination of mechanical and physical properties, with a view to the detection and enunciation of the laws connecting them with the phenomena of resistance to flexure, distortion, and rupture.

The Board will be prepared to enter upon a more general investigation, testing such specimens as may be forwarded to the President of the Board, or such as it may be determined to purchase in open market, immediately upon the completion of the apparatus ordered, at which time circulars will be published giving detailed instructions relative to the preparation of specimens for test, and stating minutely the information which will be demanded previous to their acceptance.

The following is a list of the subjects to be investigated by the standing committees, as given in the circular issued by the Board: Abrasion and Wear; Armor-Plates; Chemical Research; Chains and Wire Ropes; Corrosion of Metals; Effects of Temperature; Girders and Columns; Iron, Malleable; Iron, Cast; Metallic Alloys; Orthogonal Simultaneous Strains; Physical Phenomena; Reheating and Rerolling; Steels produced by Modern Processes; Steel for Tools."

Insulation of Lightning-Rods.—We take from the Journal of the Telegraph a few valuable observations on the subject of lightning-rods. The insulation of lightning-rods, says the Journal, is a grave error, because the insulators to some extent arrest the flow of currents of rarefied electricity, which it is the true function of the lightning-rod to facilitate. On the other hand, the insulator amounts to nothing as a barrier against a discharge of lightning, which can either pass through it or leap the short distance between the rod and the building. The prejudice in favor of insulators arises from a misapprehension. Strictly speaking, there are no non-conductors; but that term is applied to substances which conduct very imperfectly and are subjected to violent disruptive effects when a shock of electricity passes through them. To prevent a discharge from leaving the rod and passing through the building, something more must be done than to attempt to keep it out by erecting such flimsy and insignificant barriers as insulators. The rod must be arranged so as to present points for the reception and discharge of electricity at the extremities of the building, both above and below, and the different terminations in the ground must be connected by rods lying across the roof, so that lightning can be provided with a path in an horizontal direction, which, being continuous, will be preferred to any series of detached masses of conducting matter contained within the building.

Action of Absinthe and Alcohol.—In an essay which received a prize from the French Academy of Sciences last December, Dr. Magnan states as follows the comparative action of absinthe and of alcohol: Whether injected into the stomach, pulmonary passages, cellular tissue, or vascular system, these two agents produce different effects. Essence of absinthe, in weak doses, causes vertigo and sudden contractions in the muscles of the anterior portion of the body; in strong doses, epileptic attacks and mental disorder. The well-known effects of alcohol are muscular debility, staggering, relaxation of the limbs, and finally comatose sleep, without any epileptic symptoms. Injected simultaneously, alcohol and absinthe, instead of neutralizing, intensify one another, and the absinthine phenomena are in part masked under the alcoholic. The substances used in the manufacture of the liqueur absinthe, viz., the essences of anise-seed, angelica, sweet-flag, marjoram, fennel, mint, possess no toxic action. Hence all the injurious effects of the liqueur are due purely to the wormwood. Epileptiform symptoms never follow from the use of alcohol, and they are characteristic of absinthe.

Fish-Life and the Pollution of Rivers.—The injurious effects on fish of the pollution of rivers with the refuse of gas-works have been very thoroughly investigated by Prof. A. Wagner, of Munich, and from his report on the subject we take the following account of some of his experiments. His method was to put small fishes into vessels containing well-water, different amounts of gas-water being added. In water to which one per cent, of gas-water was added, the fish became at once very restless, tried to jump out, turned or. their backs after they had been in the polluted water one minute, and were dead after the lapse of six minutes. With one-half per cent, gas-refuse, the fish became at once restless, floated on their backs after five minutes, and died after thirty minutes. With one-quarter per cent, gas-refuse they became restless after some time, floated on their backs in one hour, and were dead after ninety minutes. With one-tenth per cent, refuse, they at first remained quiet; one of them showed no change after three hours and a half, but died after the lapse of six hours; no change was observed in another, a small pike, after seven hours, but it was dead the next morning.

Lightning in an Electric Clock.—A writer in Poggendorff's Annalen describes some curious effects of lightning on the wires of an electric clock on a steeple in Basle. The wire, which was sheathed in gutta-percha and cotton, was torn away and lay about in pieces from four to forty inches in length. These pieces at first sight presented nothing worthy of note, but they were found to have quite lost their stiffness, and further examination showed that they consisted only of the sheath; the copper was entirely gone. The interior of the sheath was smooth, and the sheath itself was whole except in a few places at variable intervals, where there were minute ruptures. These were evidently the holes at which the copper had escaped—as some remains of the metal sticking in them showed. These remains distinctly proved, too, that the copper had been driven out, for the most part, in a molten state. This melting of the wire must have been instantaneous, for the molten copper was expelled before its heat could act upon the sheath. Another striking fact is that, in a portion of the wire which was inclosed for protection in a lead pipe, the copper was quite unchanged, while the gutta-percha had been fused in several places. Here the lead acted by retarding the electric current, and thus the wire had time to give up its heat to the sheath.

Influence of Camphor on Plant-Growth.—Vogel, of Munich, who has studied very closely the action of camphor on plants, says that it acts like a kind of stimulant on vegetative processes, which it accelerates and intensifies. In one of his experiments he placed a branch of flowering syringa in ordinary water, and another branch in camphor-water; in twelve hours the one drooped, while the other stood upright and even developed some of its buds. This branch did not begin to wither till after the third day. Another experiment consisted in placing in camphor-water a flowering branch of syringa which was nearly dead. In this instance the plant revived, living for some time. Similar results were obtained from experiments with seeds. Oil of turpentine was found to act like camphor. It accelerated the germinative process in seeds, but it exerted an injurious action on the after-development of the plants. Vogel remarks, in conclusion, that the process of germinating, receiving of oxygen, and giving out of carbonic acid, is identical with animal respiration. From the agreement of the vegetable processes in the early period of germination with the animal processes, it would seem to follow that stimulants would have similar effects in the two cases.

A New Deep-Sea Thermometer.—Dr. Neumayer recently exhibited to the Berlin Geographical Society a new apparatus for the determination of the temperature and of the currents at great depths in the ocean. The apparatus consists of an hermetically-sealed copper box, with an external appendage resembling a rudder. In the interior are a mercury thermometer and a compass, each inclosed in a glass receptacle, in which are admitted traces of nitrogen gas. A small electric battery completes the apparatus. When it is allowed to descend attached to a sounding-line, the action of the current on the rudder causes the apparatus to take an horizontal direction, thus indicating the set of the flow by the relative positions of compass-needle and rudder, while the thermometer indicates the temperature. To fix these indications, a piece of photographic paper is suitably disposed near the glass cases containing the instruments. Then at the proper time a current of electricity is established through the gas in the receptacles, causing an intense violet light, capable of acting chemically on the paper for a sufficient length of time to photograph the shadows of the compass-needle and the mercury column. Within three minutes the operation is complete, and then the apparatus is hoisted and the paper removed.

Absorption of Water by Growing Grain.—M. Marie-Davy has been making some exact measurements of the quantity of water consumed by grain during its growth. He found that corn in pots, filled with earth and watered daily, consumed 1,796 grammes of water daily to produce one gramme of grain. According to this, a yield of thirty hectolitres (eighty bushels) of corn per hectare (two-fifths of an acre) would take up a quantity of water which, along with the water evaporated, forms a greater total than the amount of the average rainfall of Paris. Thus the yield of the land is limited by the amount of water supplied to the fields. M. Marie-Davy, however, points out that the quantity of water necessary to produce a given harvest is by no means absolute, but depends on the amount of useful mineral matters with which the water can be charged. To a certain extent water supplements manure, and vice versa. Some manures may effect a very considerable economy in the mass of water consumed.

Vegetation as a Disinfectant.—In a paper advocating the utilization of sewage for agricultural purposes, Dr. Alfred Carpenter says that, if a certain weight of rye-grass seed be sown in wet sand, without allowing the contact of any water which contains nitrogenous matter, the plants will grow to a certain size, that is, until they have used up all the matter contained in the seed, and then growth is, to a great extent, arrested. This has been shown experimentally by growing rye-grass under glass. All growth has been arrested for want of nourishment. On adding to the water solutions of fresh organic matter (meat-juice), the plant has at once begun to grow, and in a few days has doubled its size, while a test set of plants to which such organic matter has not been added has remained stationary. Another basia and glass cover with sand not containing rye-grass, but to which organic matter had been added, became putrid in a few days, but no such putridity appeared when the rye-grass was growing. A fourth case had put into it an amount of nitrate of ammonia corresponding to the amount estimated to be contained in the meat-juices which were used in the first case; but here the growth of the plant was by no means so luxuriant as when the living nitrogenous matter was added: although a fresh start was made, the plant soon dwindled away and died. Thus it appears that living vegetation acts as a powerful disinfectant, assimilating directly the nitrogenous principles of organic substances.

Nutritive Value of Cocoa.—The nutritive constituents of cocoa correspond very closely with those of beef, and largely exceed those of milk and wheaten flour: hence the importance of this substance as an article of food. In this respect it differs widely from tea and coffee, which are, perhaps, rather condiments and stimulants than foods, or flesh-formers. The following table, drawn up by Mr. John Holm, of the Edinburgh Chemical Society, shows the position of cocoa as compared with three other well-known articles of food:

ARTICLES. Cocoa. Milk. Meat
Fat. 50.0 3.5 2.87 1.2
Azotized substances. 20.0 4.0 20.75 14.6
Starch. 7.0 59.7
Gum. 6.0
Sugar. 4.3 7.2
Water. 5.0 87.5 67.80 13.2
Salts. 4.0 0.7 5.6 1.6
Woody fibre. 4.0
Cellulose. 1.7
Coloring-matter. 2.0
Ash. 1.60 0.8
Extractive matters. 1.38
Theobromine. 2.0
Parts. 100.0 100.0 100.0 100.0

"Thus," observes Mr. Holm, "although one-half of the weight of cocoa consists of cocoa-butter, it still presents 20 per cent, of albuminoid material, as against 4 per cent, in milk, 20.75 in beef, and 14.6 in wheat. In addition, it contains starch, which is present neither in milk nor beef, but in smaller proportion than in wheat." The value of cocoa as a food is thus apparent, and fully justifies the high eulogiums which have been passed upon it.

Statistics of Suicide in Prussia.—The number of suicides occurring in the kingdom of Prussia during the four years preceding 1873 is given as follows in the official journal of the Statistical Bureau:

SUICIDES. 1869. 1870. 1871. 1872.
Males 2,570 2,334 2.183 2,363
Females 616 629 540 587
Total 3,186 2,963 2,723 2,950

From this it would appear that either the female sex is less exposed to the temptation of suicide, or resists that temptation better than the male. The table shows that the frequency of suicide increases with age. This is true with regard to the whole number of suicides, not with regard to those of each sex taken separately. Thus suicide is most frequent among males between the ages of ten and fifteen, and again between fifty and sixty, while among females it is most frequent between fifteen and twenty, and again after seventy. Of suicides, married persons constitute 452 per 1,000, unmarried, 339 per 1,000, and the remainder is made up of widows, widowers, divorced persons, etc. Mental disease is by far the most frequent occasion of suicide. Religious belief does not appear to have any marked influence. On the other hand, the influence of various avocations is very evident. The favorite modes of suicide are, in both sexes, hanging and drowning—the latter more frequent in the case of females; then by fire-arms on the part of the males, by poison on the part of the females.

Defects of the Human Eye.—The human eye, because it is practically achromatic, has been supposed to be absolutely so. But it is not difficult to show that the organ is not faultless in this respect. The subject was recently discussed in a lecture by Prof. H. McLeod, at the London Physical Society, and the lecturer cited many facts to show that the eye is not achromatic. Thus to short-sighted persons the moon appears to have a blue fringe. In using the spectroscope, the red and blue ends of the spectrum cannot be seen with equal distinctness without adjusting the focusing glass. A black patch of paper on a blue ground appears to have a fringed edge if viewed from even a short distance; while a black patch on a red ground, when observed under similar conditions, has a perfectly distinct margin. It is interesting to note that Wollaston considered that the colored bands of the spectrum were really divided by the black (Fraunhofer) lines, and his statement, that the red end of the spectrum does not appear to have a boundary-line "because the eye is not competent to converge the red rays properly," shows that he had very nearly, if not quite, discovered the achromatic defects of the eye. An experiment was exhibited by Prof. McLeod to show the relative distinctness of a dark line on grounds of various colors. A wire was so arranged that its shadow traversed the entire length of the spectrum, which was thrown on a screen by an electric lamp. Viewed from a short distance, the edges of the shadow appeared to be sharp at the red end, but gradually became less distinct, until at the blue end nothing but a blurred line remained.

Infrequency of Pulse.—A case of extraordinary infrequency of pulse was recently mentioned by Mr. Pugin Thornton, at a meeting of the Clinical Society of London. The subject was a woman, twenty-nine years of age, thin and anæmic, and suffering from severe inflammation of the larynx, for which the operation of tracheotomy was performed. Just before the operation her pulse was 40, and after it she had an epileptiform attack. She was discharged from the hospital much improved, but was readmitted soon afterward. Her pulse was then found to be beating only at the rate of 16 per minute, the pulsations being strong. The frequency increased slowly for a month, when it was 20, and soon afterward it was again 40. This was some two years ago. Her pulse is now 48, and the patient has grown stout. Normally, the number of pulsations per minute differs at different periods of life: at birth, it is about 135; at the age of seven, from 80 to 85; in adults, 70 to 75; in old age, from 50 to 65. In females, the pulse is quicker than in males.

Ornamentation of Copper and Bronze.—A new mode of ornamenting bronze or copper work is described as follows: After the object has received the desired form, the drawings are made with water-colors, the body of which is white-lead. Those portions of the surface which are not painted are covered with varnish. The article is then placed in dilute nitric acid, whereby the paint is dissolved, and the surface of the metal is etched to a certain depth. The article is then washed with water, and immediately placed in a silver or gold bath, and a layer of the precious metal deposited by electricity on the exposed portions. When the latter operation is finished, the varnish is removed, and the whole surface ground or polished, so that the ornamented portion is just even with the rest of the surface. A specially fine effect is obtained by producing a black bronze of sulphuret of copper on portions of the surface between the silver ornaments. A copper vase then has three colors, black and white drawings on a red-brown ground of suboxide of copper.

Ancestors of the Esquimaux.—Charles E. DeRance, in one of his papers on "Arctic Geology," points out some of the many striking resemblances between the modern Esquimaux and the paleolithic man of Southern France. These two peoples, separated so widely in time and space, were alike in their artistic feelings and methods of incising, on tusks, antlers, and bones, representations of familiar objects; alike also in their habit of splitting bones for marrow, and accumulating them around their dwellings; in their disregard for the sepulchre of their dead; in their preparation of skins for clothing, and in the pattern of the needles used in sewing them together; alike also in their feeding on the musk-sheep and the reindeer, and in countless other characteristics. It is wellnigh impossible to resist Prof. Dawkins's conclusion that the Esquimaux is the descendant of paleolithic man, who retreated northward with the arctic fauna with which he lived in Europe.

Antidote to Atropia.—Dr. G. Rückert has made the interesting discovery that the poisonous alkaloid muscarin (extracted by alcohol from the mushroom Amanila mitscaria) is a perfect antidote to atropia, and vice versa. The pupil of the eye, enlarged by atropia, is contracted by muscarin. So, too, the depression of temperature induced by subcutaneous injection of muscarin is counteracted by the other alkaloid similarly injected. The heart of a frog, whose action had ceased from thirty to sixty minutes under the influence of muscarin, had its activity restored by the exhibition of atropia. The relation of quinine to the specific poison of intermittent fevers is probably analogous to that between these two alkaloids.