Popular Science Monthly/Volume 49/June 1896/Fragments of Science

From Wikisource
Jump to: navigation, search
Fragments of Science.

Some New Observations on Underground Temperatures.—Some recent observations on underground temperatures are described in the December number of the American Journal of Science by Prof. A. Agassiz. He says: "For several years past I have, with the assistance of Mr. Preston C. F. West, been making rock temperature observations as we increased the depth at which the mining operations of the Calumet and Hecla Mining Company were carried on. We have now attained at our deepest point a vertical depth of 4,712 feet, and have taken temperatures of the rock at 105 feet; at the depth of the level of Lake Superior, 655 feet; at that of the level of the sea, 1,257 feet; at that of the deepest part of Lake Superior, 1,663 feet; and at four additional stations, each respectively 550, 550, 561, and 1,256 feet below the preceding one, the deepest point at which temperatures have been taken being 4,580 feet. We propose when we have reached our final depth, 4,900 feet, to take an additional rock temperature, and to then publish in full the details of our observations. In the meantime it may be interesting to give the results as they stand. The highest rock temperature obtained at the depth of 4,580 feet was 79° F.; the rock temperature at the depth of 105 feet was 59° F. Taking that as the depth unaffected by local temperature variations, we have a column of 4,475 feet of rock with a difference of temperature of 20° F., or an average increase of 1° F. for 223·7 feet. This is very different from any recorded observations. Lord Kelvin, if I am not mistaken, giving as the increase for 1° F., fifty-one feet, while the observations based on the temperature observations of the St. Gothard Tunnel gave an increase of 1° F. for sixty feet. The calculations based upon the latter observations gave an approximate thickness of the crust of the earth in one case of about twenty miles, in the other twenty-six. Taking our observations, the crust would be over eighty miles, and the thickness of the crust at the critical temperature of water would be over thirty-one miles, instead of about seven and 8·5 miles as by the other and older ratios. . . . The holes in which we placed slow registering Negretti and Zambra thermometers were drilled, slightly inclined upward, to a depth of ten feet from the face of the rock and plugged with wood and clay. In these holes the thermometers were left from one to three months. The average annual temperature of the air is 48° F.; the temperature of the air at the bottom of the shaft was 72° F." A possible source of error in these observations arises from the free access which the surface air has to the mine, and the probable effect which it must exercise on the rock temperature for many feet about it. This is, of course, also true of the previous observations, conducted in mines or tunnels. Another feature which would perhaps introduce a source of error is the close proximity of the enormous mass of water in Lake Superior. It seems probable that the rock temperature in this whole region is largely modified by the vast body of water in the lake system.


The Northern Appalachians.—A concise, satisfactory summary of the characteristics of the northern Appalachian Mountain ranges is given by Mr. Bailey Willis in a paper published in the series of Monographs of the National Geographic Society. Instead of being marked by a central crest, as is usually the case, these ranges are characterized by a central zone, the surface of which is lower than the ranges on either side. This zone is a very complex valley, or series of valleys, and is known by different names in different sections of its length of a thousand miles. Two principal ranges bound it—one on the southeast, generally known as the Blue Ridge, and the other on the northwest, known as the Alleghany Front. They extend in two nearly parallel lines about seventy-five miles apart, and have each its special characteristics. The rivers flow either to the Atlantic or to the Ohio River. The divide between these groups of streams is winding and often inconspicuous, and has no definite relation to the principal heights. The Delaware, Susquehanna, and Potomac rise west of the Alleghany Front, which they cross, and, continuing eastward, traverse the Alleghany ridges and the Blue Ridge to reach the Atlantic. From among the Alleghany ridges of Virginia the James and Roanoke flow through the Blue Ridge eastward. New River, on the contrary, has its source east of the Blue Ridge in North Carolina, and runs northwest across the Blue Ridge, the Alleghany ridges, and the Alleghany Front, to the Ohio. It is thus a general fact that the streams of the Appalachian ranges are not controlled by the mountains. The ridges pursue their courses, and the streams, passing across the ridges, pursue independent courses. The discordance is one of the most marked features in the topography, and it gives rise to many picturesque water gaps. It is due to the fact that the transverse river channels are older than the valley ridges. Within the valley the brooks and creeks have arranged themselves usually in systems of pairs. Flowing southwest, a brook meets its fellow running northeast, and together they turn southeast or northwest to traverse a ridge. In the valley beyond the ridge they are joined by a pair similar to their own courses before their union. Beyond a second ridge or a third, the growing creek may for a time flowing northeast or southwest, but it will presently pass out by another water gap. Ultimately it falls into one of the great transverse rivers. This arrangement of parallel brooks which swell the volume of a creek generally flowing at right angles to their courses, resembles a vine from whose central system branches are trained on a trellis. Although most conspicuously developed in the Alleghanies, this trellis system of drainage is common in regions where beds of hard rock lie steeply inclined to the general surface. The parallel branches of the system are controlled by the parallel ridges between each two pairs. Thus it appears that the hard rocks have to this extent influenced the arrangement of the streams.


Petroleum-Lamp Accidents.—The recent report of Mr. Alfred Spencer, an officer of the control department of the London County Council, on petroleum lamp accidents, and the measures necessary for preventing them, is a very important and practical document. His conclusions regarding their safe construction and proper management are as follows: (1) The oil reservoir should be of strong metal, properly folded and soldered at the joint, and should not be of china, glass, or other fragile material. (2) There should be no opening between the reservoir and the burner, other than through the tube which holds the wick, and this tube should be extended to within a quarter of an inch of the bottom of the reservoir, and should have no opening into the reservoir except at its base. (3) The burner should be securely attached to the reservoir, preferably by means of a strong and well-made screw attachment. (4) There should be no openings through which oil could flow from the reservoir should the lamp upset. (5) Every table lamp should have a broad and heavy base, to which the reservoir should be strongly attached. (6) Wicks should be soft and not tightly plaited, and should quite fill the wick-tube without having to be squeezed into it. (7) Wicks should be frequently renewed, and before being put into lamps should be dried at a fire and then immediately soaked with oil. (8) The reservoir should be filled with oil before the lamp is lit. (9) The lamp should be kept thoroughly clean, all oil should be carefully wiped off, and all charred wick and dirt removed, before lighting. (10) When first lit, the wick should be partially turned down, and then gradually raised, (11) The wick should not be left turned down, as there is then a greater liability to explosion in lamps of unsafe construction. (12) Lamps which have no extinguishing apparatus should be put out as follows: The wick should be turned down until there is only a small, flickering flame, and a sharp puff of breath should then be sent across the top of the chimney, but not down it. (13) Cans or bottles used for oil should be free from water and dirt, and should be kept thoroughly closed.


The Serum Treatment of Disease.—It is stated in the British Medical Journal that the serum treatment of disease probably originated in the observation made by Von Fodor, in 1887, that blood when drawn from the body had a distinct bactericidal action. "Nuttall and others then pointed out that although this bacteriological action might be connected with the corpuscles of the blood, it was not confined to them, as the serum of freshly coagulated blood was found to contain some proteid substance which undoubtedly exerted a powerful bactericidal effect. In July, 1889, Babes and Lepp recorded a number of experiments in which they had found that the blood of dogs which had been vaccinated against rabies exerted a distinctly protective action when injected into susceptible animals, either previous to or along with the virus procured from a rabid animal. Ferran appears to have been the next observer to accentuate this point. He was followed by Bouchard in France, while Behring and Kitasato in Germany, and then Roux in Paris, and others in rapid succession pointed out that there was in the serum of the blood of animals vaccinated against diphtheria and tetanus a distinct prophylactic and curative agent which, however, it was difficult to separate from the serum. In 1891 patients were treated in Berlin with a serum prepared by Behring, and since then this serum has been prepared and used in nearly all civilized countries."


Infected Drinking Water.—There is a growing tendency among physicians to belittle the purely chemical examination of potable water, and to rely solely upon the results of the bacteriological tests. A recent episode, the result of which seems at first sight to strengthen this view, occurred during the trials undertaken by the London Local Government Board, in which water samples, purposely inoculated with typhoid germs, were sent for analysis to one of England's leading chemists, and were by him pronounced pure. The obviously weak point in drawing such a conclusion from the above occurrence lies in the fact that such a sample of water would not be found in practice. The mere fact that it contained no sewage, to detect which is the chief purpose of the chemical analysis, would almost certainly in practice preclude the typhoid bacillus, the pure culture being only a laboratory product. The same is practically true with all the pathogenic micro-organisms which are liable to occur in drinking water. The chemical ingredients which the sewage supplies are quite essential for the rapid growth and multiplication of the bacteria. In fact, a favorable breeding ground is perhaps not second in importance to the presence of the germ itself, as the number of individual microbes, up to a certain point, which gain access to the human body, is probably of much more importance than the kind of germ. "The chemist," says Prof. W. P. Mason, in an article in the Journal of the American Chemical Society, "is unable to say whether or not a sewage-laden water is disease-bearing on any particular date, for to him all sewage is alike, but be condemns the water for the reason that, although it may be harmless to-day, it is impossible to predict what may be its condition to-morrow. Within the week I have been requested to make a bacteriological examination of the water of a certain well, in order to determine if it be affected by neighboring cesspools. The physician who made the request was impressed with the belief in the paramount value of such an examination and the comparative uselessness of chemical analysis. I am quite convinced that, had I followed his suggestions, I should have sought in vain for any specific microbe, but inasmuch as, upon chemical analysis, I found that the chlorine ran twenty-four parts per million, which is about ten times the local 'normal,' and the 'nitric nitrogen' read nine parts per million in place of 0·116, I condemned the water offhand without going further. . . . As Dr. Dupré has pointed out, chemistry in such cases anticipates what may happen in the future, and by timely advice may prevent an outbreak of disease; while, on the other hand, the discovery of disease germs in a water is only possible after the water has become infected."


A New Low-Temperature Apparatus.—A most interesting and important demonstration of the efficiency of the process of self-intensification of cold produced by expansion alone without the aid of any extraneous artificial refrigeration is described in a recent issue of Nature. The apparatus consisted of three coils of narrow copper tubing arranged concentrically in a metal case, and connected successively together. The gas, say oxygen, enters the outer coil at a pressure of one hundred and twenty atmospheres, passing from this into the second, and from this into the central coil, which is surrounded by a cylindrical glass vacuum-jacketed vessel as devised by Prof. Dewar. The two outer coils are separated from each other by vertical divisions of the case, and the spiral of the central coil is followed by a flat spiral of sheet copper. When the gas reaches the extremity of the central coil, it escapes through a fine orifice of peculiar construction, formed by bringing two knife edges closely together. The size of the orifice can be regulated by means of an ebonite rod, which passes up the axis of the apparatus, and terminates in a handle at the top. After its escape the whole of the gas cooled by expansion passes through the spaces surrounding the pipe in which the compressed gas is passing to the point of expansion, and so makes this gas, still under pressure, cooler than it was itself while under compression. The compressed gas consequently becomes, at the point of expansion, cooler than that which preceded it, and in its turn follows backward the course of the still compressed gas, and so makes the latter cooler than before expansion, and also cooler than ever after expansion. This intensification of cooling (always assuming sufficient protection against access of heat from the outside) is only limited by the liquefaction of the gas, the temperature of liquefaction being in the case of oxygen 180° C. The apparatus exhibited measures twenty-eight inches deep by seven inches in diameter, and when once cooled down—that is, in about half an hour—it yields liquid oxygen at the rate of about seven cubic centimetres in four minutes.


How Opium is Prepared.—The English consul at Ispahan gives the following description of the process: The people commence to collect the drug early in May. The poppy head is lanced in the afternoon, and the opium which exudes and dries during the night is collected into copper pots early the following morning. It is kept in store in these pots until required for exportation. Then it is taken out of the pots and sorted. For the succeeding manipulations, each workman has a smooth board, about twenty-three inches long and eleven inches broad. He takes from the bulk about one pound of the crude opium, and rubs it on the board for a short time, then puts it in the sun for ten minutes, and afterward takes it into the shade and rubs it continuously with an iron implement something like a small solid spade, until it dries up to a certain degree. It is then collected into a mass and heated in trays over a small charcoal fire until plastic. Each man then takes about a quarter of a pound, and kneads it again on the board until it dries up to the standard degree and assumes a golden yellow color. It is next made up into cakes of one pound each, which are wrapped up in paper and placed in tin boxes, in layers alternating with poppy chaff. These tin boxes are packed in wooden ones covered with hide and gunny, and the opium is then ready for exportation.


The Finger-print Method of Identification.—In a recent letter to Nature, Kumagusu Minakata gives some interesting data, which seem to indicate that the ancient Japanese use of finger marks on divorce papers, as a means of identification, which the author described several years ago in the same periodical, was probably adopted from the Chinese Laws of Yung-Hwui, somewhere about 650 a. d. He has found a passage in the Arabian Relation des Voyages by one Sulaiman, who made several voyages to China and India in the middle of the ninth century a. d. (the time in which the above-mentioned dynasty in China was going to decline), describing the Chinese method of drawing up a contract: "The Chinese respect justice in their transactions and in judicial acts. If a man lends a sum of money to some one, he puts it down in writing. The borrower, in his turn, makes a similar writing, which he marks with two of his fingers together, the index and the middle finger. The two papers are put together and folded. Some characters are written across the portion where they join. They are then unfolded, and the writing by which the borrower acknowledges his debt is given to the lender. If, at a later time, the borrower denies his debt, he is told to bring the writing of the lender. If he pretends not to have it, and says he has never written a paper accompanied by his signature and his mark, and that his writing has been destroyed, they say to the borrower who denies his debt: 'Declare in writing that that debt does not concern you. But if the creditor proves that which you deny, you will receive twenty blows on the back, and will pay an amend of twenty thousand (fakoudj) pieces of copper.'" The antiquity of this custom is of especial interest just at present, because of the rise into prominence of the so-called Bertillon system of identifying criminals, which is based on the finger-print method.


Solid Air.—In a recent address on The Liquefaction of Air and Research at Low Temperatures, before the Chemical Society, Prof. J. Dewar gave some very interesting descriptions of such unusual substances as "solid air" and "liquid hydrogen." He says: "If a litre of liquid air be exhausted in a silvered vacuum vessel, half a litre of solid air may be obtained and kept solid for half an hour. The solid is at first a stiff, transparent jelly, which, when placed in a magnetic field, has the still liquid oxygen drawn out to the poles, showing that solid air is a nitrogen jelly containing liquid oxygen; solid air can only be examined in a vacuum, or an atmosphere of hydrogen, because it instantly melts on exposure to the air, causing an additional quantity of air to liquefy. It is strange to see a mass of solid air melting in contact with the atmosphere, and all the time swelling up like a fountain. . . . A small ignited jet of hydrogen burns continuously below the surface of liquid oxygen, all the water produced being carried away as snow. . . . By means of a jet of liquid hydrogen, liquid air and oxygen were transformed into hard white solids resembling avalanche snow, quite different in appearance from the jellylike mass of solid air got by the use of the air pump." The only widely distributed element which has not yet been liquefied is fluorine.


Curious Verbal Customs in Madagascar.—A curious custom—said to be common throughout the country—of changing names and words, is described in J. T. Last's Notes on the Languages Spoken in Madagascar. The mention of the name borne by the king while living is tabooed after his decease, and violation of this law may be punished even with death. The name of a chief is tabooed to all in any way connected with him, and that of a notable person to all belonging to his family; and should there be another person in the family bearing the same name as that of the person deceased, that name must be laid aside and another one taken. This change of name is often made as a mark of respect for a friend. It is considered an honor to the dead man to change one's name. The author while traveling once heard some guns fired off in the distance denoting death. He found, on inquiry, that the deceased was a grown-up daughter of a certain person; but the people were careful not to mention her name, because it was to be changed, and they did not yet know what new name would be adopted for her. The names given to deceased kings and chiefs are invariably formed of three words, of which the first is always Andriana—lord; the second some word denoting respect or honor, or pointing to some characteristic of the deceased; and the third and last, arivo—a thousand. Even among the common people it is considered highly indecorous to mention the name of a deceased person. Some special words are the exclusive property of kings and queens. Besides these, a number of words are common to kings and chiefs, but can not be used in the same manner by the other people. Again, the king has power to make certain words "fady," that is, to prohibit their use either for a time or entirely; and then other words must be adopted to be used in their place. Changes are often made in the use of words by the prohibition of words containing part of the name of the king or queen. These customs may be made to account for some of the differences existing between neighboring dialects; and their value as factors may be estimated when we consider the number of petty kings in Madagascar, and remember that the rules as to the name of each produce more or less permanent changes in the language.


The Deepest Sounding yet made.—It is stated that Captain Balfour, of H. M. S. Penguin, has obtained three soundings of over five thousand fathoms. They were taken in the Pacific Ocean at the following points: Latitude south, 23° 39°; longitude west, 175° 4', 5,022 fathoms, at which point the wire broke; latitude south, 28° 44'; longitude west, 176° 4', 5,147 fathoms; and latitude south, 30° 28'; longitude west, 176° 39', 5,155 fathoms (30,930 feet). The usual abysmal red clay was brought up by the sounding tube on the two latter occasions. Mr. V. Thorpe, surgeon of the Penguin, reports a microscopic examination of the specimen from 5,147 fathoms, which shows that the remains of siliceous organisms are almost if not entirely absent. The mineral particles are in a minute state of disintegration, and consist of exceedingly fine flocculent matter, mixed with pumice and other glassy volcanic products, green crystals of augite, and reddish crystals of pelagonite. The deepest trustworthy sounding previously made was 4,655 fathoms, obtained by U. S. S. Tuscarora near Japan in 1874.


Scientific Acquisitions from the Peary Expedition.—While adverse circumstances made it impossible for Lieutenant Peary to carry out, in full, his plans with reference to the northwest coast of Greenland, he, nevertheless, as Mr. Rollin D. Salisbury has shown in Science, accomplished much during his arctic residence. He twice crossed the ice cap from Inglefield Gulf to Independence Bay, and gathered information of singular value concerning the inland ice and the ice-free territory beyond. He mapped a considerable stretch of the coast from Cape Alexander to Cape York, or from latitude 78° 10' to 75° 55', covering eight degrees of longitude, and with indentations, prominences, and islands one thousand miles in length. This map includes so many features not given in the other maps that it is hard, at first sight, to recognize the identity of the regions. Eleven before unknown islands were accurately located, and the position, shape, and size of those heretofore represented were corrected. Possibly a hundred glaciers were located with approximate accuracy within a region where only ten were represented—not always correctly—on the published chart. Astrup's map of Melville Bay was prepared while its author was a member of Lieutenant Peary's company. A series of accurate and elaborate meteorological records was kept up, in which, besides the formal entries, observations were noted of the behavior of the winds about the ice sheet, presenting facts which may be of use in the study of the problems of glacierology. Measurements were made of the rate of motion of one of the most active glaciers of the region, and continued so long as to render them of special value. Two large meteorites were brought back for study. Lieutenant Peary enjoyed rare opportunities of personal contact and association, by living with them, for studying the Eskimos of north Greenland, and intends to publish the results of his studies. Much has been gained, further, through the expeditions which Lieutenant Peary caused to be sent into northern waters. Prof. L. L. Dyche, who joined the party in Greenland, secured valuable zoölogical collections of birds, walruses, reindeer, seals, and narwhals. Mr. Salisbury made observations and studies of the geographical and geological features of the west coast of Greenland, between latitudes 69° and 78° 45', at close range from the vessel, and at numerous stopping places. Many glaciers were studied in detail, determinations respecting glacier motion were made, evidence was gathered touching the former extension of the ice cap of Greenland, and determinations were made concerning recent changes of level in the land.


Micronesia.—The following description is taken from a paper on the Marshall Islands, read before the Berlin Geographical Society on June 8, 1895: "The Marshall group consists of two nearly parallel series of islands, running from north-northwest to south-southeast, which are named by the natives Ratak (Islands toward the Dawn) and Relik (Islands toward the Sunset). The group covers about one hundred and seventy-six square miles. All are coral islands and most of them atolls. Of the Relik group the most important are Yaluit (the seat of government). Ebon, and Namvik. Of the Ratak group, Mejem has a population of about twelve hundred. The climate is, for a tropical region, comparatively favorable to Europeans. There are no swamps, but the continued high temperature and the moisture of the air render them dangerous for Europeans with heart or lung disease. Besides affections of the heart and kidneys, dysentery and rheumatism (both of the muscles and joints) are not uncommon. Observations extending over three years gave the mean temperature as 80·6° F., the extremes being 93° and 71°. The rainfall is pretty evenly distributed throughout the year, and is quite excessive (one hundred and seventy-seven inches). It is only in January and February that a comparatively dry period can be expected. The northeast trades blow from December to April, becoming rather easterly or southeasterly from March to November. Calms or violent southwesterly storms occur chiefly between August and November. There being no springs, a supply of water is collected in tanks or cisterns. The useful plants include the cocoanut palm, breadfruit tree, and Pandaus odoratissimus, the sap of which last is rich in sugar. The cultivation of plantains has much increased of late, besides which several kinds of arums, the South Sea arrowroot (Tacca pinnatifida) and a mangrove which supplies a black dye are grown. Guavas, figs, citrons, and anonas thrive well, but tea, coffee, cacao, etc., can not be grown at all. The Micronesian population amounts to from twelve thousand to thirteen thousand. The population belongs to four sharply defined classes. The great mass consists of the common people (Kayur); the next higher class is that of the Leatakketak, comparable to village magistrates, who see that the orders of the chiefs are carried out. Neither of these classes own land, but they are allowed to grow as much produce or catch as much fish as is necessary for their sustenance. The ordinary chiefs (Burak) rank above both these classes, and they often possess larger holdings than the head chiefs (Iroj). All the members of these four classes acquire their rank through the mother only. The race seems to be deteriorating physically, owing to the prevalence of specific disease, with which about fifty per cent of the inhabitants are afflicted,"