Popular Science Monthly/Volume 22/February 1883/Popular Miscellany

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Observations of the Recent Transit of Venus.—Professor C. A. Young has published in the "New York Times" a summary of the results, so far as they can be estimated so soon, that have attended the observations of the transit of Venus of December 6th in this and other countries. On the whole, he says, the observations were successful beyond expectation. Although in the United States there was more or less cloudiness, there were very few stations that did not succeed in accomplishing the most essential portions of their intended work. The first contact, although it is the most difficult part of the phenomenon of which to get an accurate observation, and although it was not seen by more than half as many observers as the other three contacts, was noted by some of the observers at twenty out of the thirty-nine stations on the continent where it might have been visible. An unusually satisfactory observation was obtained at Princeton. The other contacts were observed with more general success, the second at twenty-nine, the third at thirty-two, and the fourth at thirty stations. As far as can be judged from the present incomplete calculations, "it would appear that the planet was about 20" to 25" behind time in her orbit, and that her diameter assumed in the computations was at least 1", and probably 1·5", too large. The duration of the transit appears, also, to have been about 25" longer than computed, which might indicate either of two things or a little of both—that the planet was 1" or 2" of an arc north of its computed position, or that the diameter of the sun is a trifle larger than was assumed. The agreement, however, was remarkably close." Heliometer observations were made by German parties at Hartford, Connecticut, and Aiken, South Carolina, and by Professor Waldo, at Yale College. Measurements of the sun's diameter by similar or somewhat different instruments were also made by the French at St. Augustine, the Belgians at San Antonio, and—with a wonderfully simple but accurate apparatus—at Cambridge and New Haven. Photographs were taken by different methods at a number of places, and with unexpected success, except at Washington. "At Fort Selden and at the Lick Observatory the day was perfect, and the photography went on without a hitch." Micrometric observations for the diameter of Venus were made at fifteen or sixteen stations on this continent, and perhaps at nearly as many more foreign stations. The results are not yet reduced, but the indications correspond with the conclusion, which was drawn from the contacts, that the planet's diameter is really considerably smaller than has hitherto been assumed. The photometric observations showed that Venus was distinctly darker than the sky just outside of the sun's limb. The results of the spectroscopic observations at Cambridge, South Hadley, Princeton, and Alleghany were "purely and surprisingly negative," and showed for the most part no conspicuous evidence of selective absorption by the planet's atmosphere. The Princeton observers, however, were so fortunate as to find distinct indications of water-vapor, thus confirming certain old observations of Huggins. Professor Langley, at Alleghany, observed a spot of abnormal brightness in a part of the atmosphere of the planet where such an appearance would be least expected, which may denote auroral and magnetic phenomena. Professor Harrington, at Ann Arbor, made out spots and markings on the planet's disk, but no one else has spoken of them. In Europe the weather was generally bad. Good observations were made, however, at Potsdam, Prussia. The reports so far received from the southern hemisphere are most gratifying; and, whatever it may be with the stations yet to be heard from (chiefly near the Straits of Magellan), "enough is already secure to make it certain that we have observations sufficient in number and character to test the full value of the transit as a means of determining the solar parallax." It must be several years, however, before the observations can be fully reduced and published, and the exact results ascertained.


Work of the Dearborn Observatory.—The great equatorial of the Dearborn Observatory, Chicago, was employed during 1881, under the direction of Professor G. W. Hough, chiefly in the observation of the great comet of the year, the planet Jupiter, the satellites of Uranus, and difficult double stars. A drawing of the nucleus and envelope of the comet, showing the peculiar formation of the head and surrounding envelopes, was made on the 23d of June by Professor Colbert, who also first announced the distance of the comet from the earth. In attempting to reconcile the various phenomena alleged to have been seen on the disk of Jupiter, the greatest difficulty is found to exist in determining what is real and what is imaginary. Contemporaneous sketches by different persons, or even two by the same observer, show such marked discrepancies that they are of but little use in ascertaining suspected changes. The observations made here during the past three years confirm the statement that the changes on the disk of the planet are slow and gradual. The attempted observations on the inner satellites of Uranus were impeded by unfavorable night weather. About two hundred and fifty micrometer measurements of double stars were made, including nine measurements of the companions of Sirius. Sixty difficult double stars, not found in the catalogues, were discovered, including two quadruple systems and one naked-eye star, with a very minute companion. Mr. S. W. Burnham is preparing for publication a catalogue of one hundred and fifty-one double stars discovered at the observatory during the past three years; also, a compilation of all the star observations made by him during the same period, comprising about twenty-five hundred measurements. The observatory is open to members of the Chicago Astronomical Society on Thursday evenings; and classes from the city high-schools and elsewhere are occasionally admitted.


The Poles of Extreme Cold.—There appear to be two districts on the northern hemisphere, widely separated from each other, in which the coldest places on the earth are to be found. One is in Northeastern Siberia, the other in the American Arctic Archipelago. The particular points within these regions, that have the property of being colder than all surrounding points, may be called the poles of extreme cold. Their geographical situation is not precisely ascertained, because a sufficient number of observations have not been made, but enough is known to make it safe to conclude that the Asiatic pole is north of Yakutsk, and the American pole northwest of the Parry Islands, toward Eastern Siberia. The Asiatic pole is upon the mainland, the American pole in a sea studded with islands; and from this the two regions derive distinct climatic characters. Near the Siberian pole, which lies in the comparatively low latitude of from 60° to 70°, the continental climate is exhibited in an extremely cold winter and a warm summer, while the more maritime climate of the American pole, which lies between 65° and 68° of latitude, is expressed in a relatively milder winter and cooler summer. Yakutsk has hitherto been considered the coldest place on the earth, it having a mean temperature in January of -45°. Colder places have since been found that have a mean temperature for January as low as -55°. They are situated in about latitude 6712° north, near Werkojansk, in Siberia. The cold-pole is located here from November till March; it then moves in April and May toward the northwest into the Arctic Ocean, between the mouth of the Obi and Nova Zembla, and afterward returns to Werkojansk. Werkojansk is the only place that lies within the isotherm of -40° during November, December, January, and February, or for four months; Yakutsk suffers this mean temperature during December and January; Ustjansk, at the mouth of the Yana, only during January; while Tolstoi Noos, at the mouth of the Yenisei, lies entirely outside of the isotherm of -40°. The mean annual temperature of the Siberian cold-pole may be estimated at 2°. A still colder place appears to have been found by M. Klutschak, of Lieutenant Schwatka's expedition, at the Adelaide Peninsula, in Cockburn Bay, latitude 66° to 68°, where the temperature in January, 1880, reached -72°; in December, 1879, and February, 1880, -68°; and in September, October, and November, 1879, 5°, -38°, and -49° respectively. The mean temperature from December to February, -48°, varies but little from that of Werkojansk, and is from 18° to 21° lower than had been previously noticed in the American cold region.—Die Natur.


Do House-Flies convey Infection?—Dr. Thomas Taylor, of Washington, has published an account of some examinations he has made into the capacity of the common house-fly to transmit disease by carrying the germs from place to place. The question is really one of exceeding importance, for, "considering the habits and habitat of the house-fly, it will appear evident that, should it prove to be a carrier of poisonous bodies, its power to distribute them in human habitations is greater than that of any other known insect. Under our system of public travel, the common house-fly may be transported from one end of the continent to the other. It may feast to-day in the markets of Washington, and to-morrow in those of New York, and in a like manner it may be transported from a hospital for contagious or infectious diseases to homes in the vicinity, or even in remote localities. It may also be taken from one hospital to another, or from one ward to another within the same hospital, and may plant the germs of disease in exposed wounds, or deposit them in food, or liberate them in the atmosphere breathed by patients afflicted by diseases of a different class." Millions of the minute germs of putrefaction could be carried to a distant city by a single fly. These considerations justify and should prompt inquiry. Dr. Taylor's attention was called to the subject by his witnessing the sufferings of a fly afflicted with anguilulæ. In the direct experiments which were suggested to him by this observation, the larvæ of flies confined in a receiver with rust-spores ate the germs. When spores were sprinkled on sugar, the insects themselves consumed both spores and sugar; but some of the spores became fastened on the legs of the flies, and were only the more closely attached by the efforts made to get rid of them. They might, however, be brushed off by objects with which they were brought in contact, while their germinating powers would long outlast the life of the insect itself. Dr. Taylor regards it as evident from his experiments that flies are capable of conveying spores to plants and other bodies, but considers that the fact that the greater part of the spores were consumed by the flies or their larvæ shows that the insect may destroy microscopic germs as well as disseminate them, and indicates that in some cases its agency in keeping down their number may more than counterbalance its action in contributing to their dissemination.


American Stature.—Mr. George W. Peckham, teacher of biology in the Milwaukee High School, has been making investigations under the auspices of the Wisconsin State Board of Health into the growth of children. From examinations and measurements made chiefly in the schools of Milwaukee he has deduced the conclusion that the relative rate of growth of the sexes is such that the boys are taller till the twelfth year and heavier till the thirteenth, after which, between thirteen and fifteen the girls are both taller and heavier. After the age of fifteen, however, the boys exceed the girls both in weight and stature. Girls cease to grow when about seventeen years of age. Children of pure American descent are taller than children of foreign-born parents, but are generally lighter in weight than children of German parents. The children of Irish parents are also taller than those of German parents. Comparing his results with those of similar observations made in Boston, he concludes that school-children in Milwaukee are taller than those in Boston, and the boys weigh more, but the girls of Boston are slightly heavier than those of Milwaukee. The superiority superiority in height of the Milwaukee children is ascribed to the inferior density of population and the existence of fewer urban disadvantages in that city than in Boston; and the general hypothesis is drawn, from Peckham's tables, that the height of American-born men is more modified by the conditions accompanying density than by all other influences, race excepted, urban life as compared with rural life tending toward a decrease of stature. The rate of growth of Germans appears to be considerably modified by residence in this country through one generation; and, in intermarriage between Americans and Germans, the offspring seem to take the height of the taller parent.


Use of the Gummy Secretions of Plants.—Inquiry has often been made respecting the functions of the secretory apparatus of plants, or that which stores up special juices, such as the resins, gums, caoutchouc, milky juices, and the waxes. Sachs, even in the last edition of his botany, places these substances among those the office of which in the economy of the plant is wholly unknown. Because the secretions in question have been observed to be poor in oxygen and generally unassimilable, they have commonly been regarded as waste matter, useless to the organism. M. de Vries is of a different opinion, and regards these substances as a kind of protective salve, and considers them helpful in the healing of wounds. Of the resin of conifers, he remarks that, if it were simply a product of secretion, the accumulation of it would not cause the tree to suffer. The extraction of resin, however, weakens pines very considerably, and diminishes the growth of wood by about one third. Accidental wounds, moreover, and even normal wounds produced by the fall of limbs or by splitting of the bark, are very numerous in conifers. Whenever a wound is produced, it is forthwith covered over with a viscous and thick mass of resin, which gradually hardens in the air. Among non-resinous plants wounds become isolated by means of a pad of healing tissue which sometimes covers the wound completely over, but often too late to effect the purpose. From this point of view, M. de Vries suggests, the conifers are superior in organization to common angiospermous trees. The organism in coniferous trees seems in a manner to have foreseen possible wounds, and a system of canals designed solely to furnish a covering for wounds seems to have been differentiated in them. In a second part of his work, M. de Vries treats of the function of the juices analogous to the resins which are found in other plants, and seeks to assimilate to the resins, from different points of view, the latex, some of the gums, caoutchouc, and waxy matters, lie shows that these substances also exude for the occlusion of wounds, even in herbaceous plants like the northern chicories and spurges, and cites some recent experiments by M. Moll in favor of his view. It would, however, be a narrow judgment to conclude with him, from these experiments, that the sole object of the secretions is the healing of wounds. M. Raumhoff, criticising the work of M. de Vries, has shown that the considerations on which his theory rests do not furnish an adequate demonstration of it. It is evident, for instance, that the purpose of the lactiferous tissues can not be solely the healing of wounds, for these tissues in the spurges contain starch, a substance that does not assist in that office, and which is not a product of secretion. The studies of M. Treub on the tropical spurges furnish evidence that one of the probable offices of their lactiferous tissues is the conveyance of starch.


The Possible Annual Yield of a Forest.—The basis on which all sound forest management depends, says Colonel G. F. Pearson, is the revenue which any forest can be made to pay—that is to say, the income which it will produce in proportion to the volume of the standing trees, or, in other words, its capitalized value. To this end a forest should be considered as so much capital, represented by so many cubic feet of wood; while the amount of wood produced each year, by its growth, represents the interest thereon, and, in fact, is the revenue of the forest. It is evident that it is possible to cut and remove every year a quantity of timber equal to this annual increase of wood, without diminishing the volume of the standard crop. The possible annual yield of a forest may be estimated on the basis of a calculation that a tree, ten feet in girth, which makes a ring of wood of only one eighth of an inch in thickness, adds to its bulk at the rate of rather more than one cubic foot of timber annually for every ten feet of the length of its stem; or, in other words, such a tree, if its stem be thirty feet in height, will, in thirty years, have increased in bulk by at least one hundred feet 01 solid timber. At the same time, during these thirty years, the young trees which are springing up will have become perfectly hardy, and capable of supporting the whole force of the summer heat and winter frost.


Marriage Customs of the Kacheen.—Mr. R. Gordon, who has been exploring among the sources of the Irrawaddy River, has given to the Royal Geographical Society some additional facts concerning the marriage customs of the Kacheen, the curious Burmese tribe who were described by Lieutenant Kreitler in the July number of "The Popular Science Monthly": "When a man and woman set up house, the man has to give to the parents of the woman cattle, pigs, gongs, muskets, das, slaves, clothes, spears, and money; and for his wife's use he has to give coral beads, tameings, jackets, broadcloths, etc., according to his circumstances. After the gifts the woman is brought to the man's house, and the man has to feast the bringers of the woman with rice, and curry, and spirits, and liquors. To the elders, also, he has to give blue waist-cloths, turbans, das, or spears, according to their degree. The man then shows the woman all the work to be done in the house, and bids her do the work. After having lived together for a long period, if the man dies, the woman can not marry any one; but the elder or younger brother has to set up house with her. If there be no brother, the deceased man's father (the woman's father-in-law) takes possession of her, and makes her his wife. If an elder brother dies, the younger brother takes over his wife. If the father dies, the son takes over his father's wives, and makes them his own, except his own mother. If a wife dies, the husband goes to her parents and asks for another wife, and they have to give him her elder or younger sister—a woman who is unmarried. If there be no sister to give, they have to give a female relative. Husbands and wives must not be at enmity with each other. Divorce is unknown as a custom. However bad husband or wife may be, they can not separate, unless, in the case of the husband, he gives double the amount of what he originally gave her, and, in the case of the wife, unless she gives quadruple the amount she originally received. If the man sets aside his wife and takes another, the head wife has the right to take possession of all the property of the younger wife, as well as to sell her. The young unmarried men and women, so long as they are not brothers and sisters, act as they please inside the apartments of the house." The Kacheen women wear waist-cloths dyed black and blue, five hands long and not very wide. The jackets are close-fitting, and over them they have a looser one set off with cowries. This is probably full dress. Round their waists they have perforated cowries on three or four hoops of rattan. From their knees down to their calves they wear hoops of rattan. Some women, the wives of the principal men, tattoo their legs from the knee to the ankle.


European Technical Schools.—Mr. Edward C. Robins has presented to the British Society of Arts the results of the inquiries he has made into the causes of the differences in the degree in which different countries have profited from technical education. The clew is not found in differences in primary education; but, when the provisions made in foreign colleges for higher education are examined, something will be found in them so superior to anything in England as to afford a lesson of value. The intellectual and social condition of the industrial population, he premises, and the character of the education it should receive to fit the national mind to cope with the national progress, can not be met by an extension of scholastic institutions, based on the requirements of the middle ages. Yet this is the principle which has dominated the universities, "and, until very lately, no concessions have been made to the reasonable demands of progressive civilization." Secondary and primary education are left in no better condition with reference to this point. The improvement in the technical education of the masses, however, which has begun in the board schools, and is destined to widen, will necessitate a like improvement in all the grades above them. The English are nevertheless gaining in artistic development, and the freedom of choice and the individuality of the English artist arc beginning to tell abroad, and English taste in architecture and ornamental design is rapidly supplanting Continental. It is to England that Germans come for Christmas-cards, original ornamental pottery, patterns for embroidery, etc.; "and, in Vienna lately, I could scarcely buy a souvenir that was not adorned with cuttings from Kate Greenaway's charming crudities." The Royal Commissioners on Technical Education show in their reports that, among the French, it is not in the technical education of the ordinary working-classes that the differences sought are to be found; and the reports of the French commissioners reveal a state similar to that prevailing in England, so far as their ordinary workmen are concerned. Schools of arts and trades have been established, but their pupils expect to be foremen, not workmen. Apprenticeship schools have also been started, with more promising results. The best and most successful technical schools are in Switzerland and Germany, and conform, as a rule, to Professor Ayrtoun's definition, that they are not a school where the manipulation or routine of a trade is taught, but one where a lad receives general instruction in the principles of applied science, and special instruction in the application of those principles to the particular trade he is following, or which he is about to follow. In them everything is taught that can be gained at the universities, except the dead languages, while modern languages and the applications of modern science to art and industry are added, with such thoroughness that nearly all the leading men of England have found it desirable to spend some years in Germany. In the Polytechnikum at Zurich, Professor Meyer teaches chemistry in a purely scientific direction, irrespective of any practical application; then Professor Lunge treats the chapters which refer to practical applications, at greater length, and enters into a number of details relating to various chemical industries, placing the technical side foremost, but laying the principal stress on explaining the scientific principles underlying the applications. Models of every kind of mechanical action and of every kind of machine are found, but manual labor is excluded; while the student in architecture, for instance, has to work out the strains of every floor or roof or specialty in construction, and to delineate the same in skeleton diagrams attached to every plan he draws; and the mechanical draughtsman is not given a subject to copy, but only the parts of a machine, which he has himself to piece together, thus thoughtfully working out in practical draughtsmanship the theory he has been taught to apply constructively. The highly educated young men from these polytechnikums finally become masters when they can, but are not ashamed, till then, to act as foremen of manufactories, etc.


M. Respighi on the Light of Comets.—M. Respighi, admitting the fact that a part of the light of comets is due to the reflection of solar light, is of the opinion that it is yet too soon to decide that any part of it is a proper light due to the comet's own incandescence. He believes that the discontinuity of the comet's spectrum, and the bright lines or bands, may proceed from light modified by passing through the masses of vapors or gases, of which the cometary bodies are composed. It is certain, he observes, that a large part of the cometary light comes from the interior of the bodies, and passes through extensive strata of vapors, in which it is subjected to a selective absorption that causes it to give lines different from the Fraunhofer lines of the sun. So we may have both the weak but complete spectrum produced by the light reflected from the outer strata in which the absorption has been insensible, and another spectrum coming from the deeper parts, with which the absorption has been greater. This view is confirmed by M. Respighi's spectroscopic observations of comet b, 1881. The phenomenon, he observes, is of a similar nature to that of the dark bands of the spectrum of the sun in the horizon, but is greatly exaggerated in the case of the comets by the enormous volume of the vapors, the richness of their chemical composition, and the feebleness of the light they reflect.


Nerve-Vibration as a Remedy.—Dr. J. Mortimer-Granville writes in the "Lancet" that enlarged experience in nerve-vibration, as a means or method of treating disease, has confirmed his belief in its value, and he has no longer any hesitation in recommending its adoption by the profession. He has employed it in a very considerable number of cases, differing widely in their nature and characteristics, and, although he has had many failures—mainly, as he believes, from errors in diagnosis, and mismanagement in the application of the treatment—"the net result has been such as to place beyond reasonable question the fact that, in precisely applied mechanical vibration of nerves and nerve-centers, we have a means of eliciting function and stimulating nutrition which surpasses for directness and rapidity of action any other system or method extant." Regarding the principles of the practice, Dr. Mortimer-Granville believes that, in the treatment of neuralgia, percussion acts simply by interrupting a morbid series of vibrations and substituting for it another series which is not morbid. Its success is by no means certain; but it deserves a trial, and particularly in cases which would otherwise be treated by nerve-stretching. The method is believed to be of the highest possible value for the rousing of torpid nerve-centers and eliciting function from the several organs of the body. Every organ "may, in the absence of disabling organic disease, be made to perform its proper function by exciting the nerve which supplies it with energy by mechanical vibration. In this way I have seen the liver unloaded, and what seemed to be inveterate torpidity of the intestines remedied in a few successive vibrations. I have now under treatment the case of a child who was six weeks ago to all appearance an idiot, but who has already developed so much cerebral activity and growing intelligence, under the influence of specific center and nerve-vibration, that I entertain the strongest hope of his ultimate awakening, and a fair approach to the normal state. A surprising amount of success has attended percussion in cases of obstinate and what was supposed to be irremediable deafness. ... In neurasthenia, neurasthenia, and even commencing sclerosis of the spinal cord with loss of tendon reflex, the most remarkable effects are produced by applying the percuteur over the spinous processes of the appropriate vertebræ."


Obituary.—Science, in California, lost by the death of the Hon. Benjamin B. Redding, State Fish Commissioner, in August last, one of its most active promoters. Mr. Redding was a Regent of the University of California, and President of the Board of Trustees of the California Academy of Sciences. He took great interest in all scientific work, especially in the paleontology of the Pacific coast, and was an indefatigable collector of prehistoric and aboriginal relics. He was also a member of the Geographical Society of the Pacific, and read before it in April last a paper describing a visit to the Galapagos Islands, made in 1850. A list of his contributions to current literature since October, 1877, contains the titles of more than eighty papers, nearly all of which had a scientific bearing. No record is preserved of his previous contributions. His papers have been described as always full of original facts, clearly and simply expressed. Mr. Redding was fifty-eight years old.