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Popular Science Monthly/Volume 53/October 1898/Fragments of Science

Fragments of Science.

Growth of Astronomical Photography.—Reviewing the history of astronomical photography in his address as vice president before the Astronomical and Mathematical Section of the American Association, Prof. E. E. Barnard credited the inception of the idea to the Rev. Thomas Dick, author of a series of astronomical works formerly much read, who, shortly after Daguerre's discovery was announced, speculated upon the practicability of applying it to the moon; thought the planets would prove easy subjects to the new process, and that something might perhaps be discovered about the nebulæ; and suggested that objects not visible to the eye might be found depicted on the plates. While much excellent photographic work has been done on the nebulæ, the photography of the planets seems to-day no nearer realization than in Dr. Dick's time. In 1839, Arago addressed the French Academy on the subject of photographing the skies, and within a year from that time Dr. Draper, in New York, had succeeded in getting a picture of the moon. Five years later Harvard College began its photographic work, and pictures of the moon were secured with the fifteen-inch equatorial. Since then this work has made great advances, to which American investigators have contributed materially. The completion of the Lick Observatory marked a decided advance in study. In photographic work on the sun, detail on the surface was first sought; the prominences next became objects of examination, and the corona was then taken up. With the application of the dry plate, students have gone back to detail on the surface and within the sun spots. A most important branch of investigation is that of stellar photography, which dates from 1882, when the astonishing number of stars shown on Dr. Gill's photograph of a comet at the Cape of Good Hope attracted attention. The work has been taken up with energy by many observatories, and most excellent results have been accomplished.

 

Officers of the American Association.—The Council of the American Association for the Advancement of Science chose Prof. Edward Orton, State Geologist of Ohio, and President of Ohio State University, to be president of the association for 1899, and Columbus, Ohio, as the place of the meeting. The following other officers, and sectional vice-presidents and secretaries, were chosen: General Secretary, F. Bedell. Secretary of the Council, Charles Baskerville. Treasurer, R. S. Woodward. Vice-Presidents: Section A, Alexander MacFarlane; Section B, Elihu Thomson; Section C, F. P. Venable; Section D, Storm Bull; Section E, J. F. Whiteaves; Section F, Simon H. Gage; Section G, Charles R. Barnes; Section H, Thomas Wilson; Section I, Marcus Benjamin. Secretaries: Section A, John F. Hayford; Section B, William Hallock; Section C, H. A. Weber; Section D, James M. Porter; Section E, Arthur Hollick; Section F. Frederick W. True; Section G, W. A. Hellerman; Section H, George A. Dorsey; Section I, Calvin M. Woodward.

 

New Elements.—Prof. Charles F. Brush, in a preliminary paper read to the American Association, described a new atmospheric gas which he discovered while examining glass for occluded hydrogen, and has found absorbed in many substances. It has been partially separated from air by diffusion. The chief characteristic of this gas thus far experimentally determined is enormous heat conductivity at low pressure. Even when mixed with a large excess of other gases, its heat conductivity is about a hundred times that of hydrogen, and this will probably be increased many times when it is obtained pure. Taking the heat conductivity at this figure—a very moderate estimate—the mean molecular velocity of the new gas is calculated to be more than a hundred miles a second, and its density only a thousandth part that of hydrogen, while the specific heat is found to be six thousand times greater than that of hydrogen. A gas having attributes anything like these could not possibly be confined to the earth's atmosphere; hence the new gas probably extends indefinitely into space, and constitutes an interstellar atmosphere. In recognition of this probability. Professor Brush has named it etherion. Professor Nasini, of Padua, and two associates report that in studying the gases emanating from the earth in various parts of Italy, with the object of detecting the presence of argon, helium, etc., they have discovered in the spectrum of the gases of the Solfatara di Pozzuoli, along with other lines deserving investigation, a fairly bright line corresponding with that of (solar) corona 1474 K, attributed to coronium, an element not previously discovered on the earth, and which should be lighter than hydrogen.

 

A Paradise for Wild inimals.—During the last four years, the London Spectator tells us, the Duke of Bedford has carried out a scheme of animal acclimatization in the park at Woburn Abbey never before attempted in England. "Birds as well as quadrupeds are the subjects of this experiment. . . . But the greater number of the animals are various kinds of deer, of which no fewer than thirty-one species are in the open park or paddocks, bisons, zebras, antelopes, wild sheep and goats, and yaks. The novelty and freshness of this experiment consist not only in the accumulation of such a number of species, interesting as this is to the naturalist, but in their way of life, free and unmolested in an English park. That is the lot of the greater number of the animals at Woburn, some being entirely free and roaming at large, like the native red deer and fallow deer, while the others, though for the present in separate inclosures, are kept in 'reserves' so spacious and so lightly though effectively separated that they have the appearance of enjoying the same degree of liberty." The general effect on the view of this gathering of animals from all quarters of the earth on the green pastures and under the elms and oaks round the home of a great English family is described as being magnificent. "During the journey back by train through Bedfordshire and Buckinghamshire, the valleys and meadows stocked with our ordinary domestic animals seem solitary and deserted after the eye has rested for hours on the varied and impressive forms that crowd the slopes, groves, and glades of this glorious park. This effect is due in part to the largeness of the scale on which the stocking of Woburn with wild animals has been carried out. In the phrase of the farmer, the park 'carries a larger head' of animals than is commonly seen on a similar area, even in the richest pastures. The scene recalls the descriptions of the early travelers in southern Africa, when the large fauna roamed there in unbroken numbers and with little fear of man. . . . From one position, looking up a long green slope toward the abbey, there could be seen at the time of the writer's last visit between two and three hundred animals, both birds and beasts, feeding or sleeping within sight of the immediate front of the spectators. These varied in species from cranes, storks, and almost every known species of swan, to wapiti stags, antelopes, and zebras, walking, sitting, galloping, feeding, or sleeping. For quite half a mile up the slope the white swan and other wild fowl were dotted among the deer and other ruminants, presenting a strange and most attractive example of the real 'paradise' which animals will make for themselves when only the 'good beasts' are selected to lie together."

 

Play and Development.—In a paper on play as a factor in development, published in the American Physical Review for December, 1897, George A. Fitz, of Harvard University, places himself upon the theory now generally accepted by those who have given the most careful study of the subject, that play is simply the most important means Nature has of preparing her children for their life work. "We can readily see how this has come about. The animals which played were able to make a better fight for existence, hence survived, and fixed in their progeny the desire to play as an instinct. Play is not merely the result of the accidental desires of the individual; it is a result of that natural selection which demands everything serviceable to the preservation of the species. Thus youth becomes more completely an apprenticeship to life, with play as the master workman. All of Nature's children play and are thereby prepared to live; not playing, they die. Granting, then, that play is one of the most powerful instincts in animal life, let us study its more intimate relations to human life. How does the child who plays vigorously and spontaneously differ from the child who plays under close restriction or not at all?. . . He is born with an inherited tendency to grow into the adult form, but this inherited force toward development is not sufficiently strong to produce unassisted more than a mimicry of the best adult form, mental or physical. The great law of development is the law of use. No organ or tissue, no power of muscle or brain, can be fully developed except through use, through effort. In the play of young animals we find all the conditions of use necessary for their highest development. In the spontaneous play of the child with unrestricted opportunities, we find again the conditions of use for all the tissues fully satisfied." Further than this, the child is habituated to make rapid judgments in the presence of ever-changing relations; there is probably no factor so potent in the balance of the nervous system; in its psychic effects it gives a complete psycho-physiological picture of pleasure. "In play, the child is the unit of force; he initiates his own conditions. His limitations are self-imposed. His self-control lies in execution rather than inhibition. He is concerned with self expression rather than with self-repression. Play thus relates itself to the truest conception of education, the development of power, the power of the individual to act as a self-directed unit in civilization. The self-control gained by play acts immediately, strongly, and honestly in response to conditions as they are presented in life."

 

The Place of Plant Physiology.—Plant physiology, as briefly defined by Prof. D. T. MacDougal, is concerned with the fundamental properties of the protoplasm of plants, and the functions of the organisms into which it is formed. It therefore includes the consideration of all reactions of growth, movement, metabolism, changes in form, instability, and other phenomena resulting from the activity of forces internal to the plant. It merges into morphology on one side, and partly underlies oölogy on the other, and with bacteriology and mycology forms the basis of the study of pathology. Physiology and chemistry join in the consideration of the chemical activities and products of the organism, and the principles of physics are involved in the investigation of the plant machine. It is too often slighted in schools by being made a text-book and routine study. "A systematic survey reveals the fact that, instead of a complete and thorough plotting of the great field of physiology, we have made here and there a few simple trails through the dense jungle of ungrouped and vaguely defined principles, and the greater part of the work is yet to be accomplished. The fundamental problem of the constitution of living matter still confronts us." We have not yet succeeded in interpreting clearly even the cruder visible phenomena of the cell. The interprotoplastic threads have so far received no conclusive interpretation. Numerous problems relating to nutrition wait for solution—the relations of chlorophyll, of the nitro-bacteria, the acquisition of nitrogen, the balance and combined action of the mineral elements in the soil, the formation and work of the alkaloids, glucosides, pigments, and other compounds in the plant, and the ascent of sap, are only a part of the subjects concerning which we are still in the dark. It is becoming more and more evident that molecular features of growth, and the relation of this process to correlative forces and those of the environment, are hardly at all determined.

 

United States Railway Statistics.—Advance sheets of the Tenth Statistical Report of the Interstate Commerce Commission are authority for the following statistics: The total railway mileage in the United States on June 30, 1897, was 184,428.47 miles, there being an increase of 1,651.84 miles, or 90 per cent, during the year. The total number of locomotives in service on June 30, 1897, was 35,986, the increase in number as com. pared with the preceding year being 36. The gross earnings of the railways of the United States for the year ending June 30, 1897, as reported for an operated mileage of 183,284.25, were $1,122,089,773. In comparison with the preceding year this amount shows a decrease in gross earnings of $28,079,603. The number of men employed by the railways of the United States on June 30, 1897, as reported, was 823,476. A com. parative summary is presented in the report of the average daily compensation of the different classes of employees for the years 1892 to 1897. Another summary is given in the report which shows the total amount of compensation reported as paid to railway employees during the fiscal years 1895 to 1897. It covers the compensation of over 99 per cent of railway employees for the several years. Regarding the year ending June 30, 1897, it appears that the aggregate amount of wages and salaries paid was $465,601,581. This amount represents 61.87 per cent of the total operating expenses of railways, or $2,540 per mile of line. The total compensation for 1896 was $3,222,950 greater. The total number of casualties to persons on account of railway accidents for the year ending June 30, 1897, was 43,168. Of these casualties 6,437 resulted in death, and 36,731 in injuries of varying character. Of railway employees, 1,693 were killed and 27,667 were injured during the year. The total number of passengers killed during the year under review was 222; injured, 2,795. Ninety-three passengers were killed and 1,011 injured in consequence of collisions and derailments. Other than employees and passengers the total number of persons killed was 4,522; injured, 6,269. Included in these figures are casualties to persons classed as trespassers, of whom 3,919 were killed and 4,732 were injured. From summaries showing the ratio of casualties, it appears that 1 out of every 486 employees was killed and 1 out of every 30 employees was injured during the year. With respect to train men, including engine men, firemen, conductors, and other train men, it appears that 1 was killed for every 165 employed, and 1 injured for every 12 employed. One passenger was killed for every 2,204,708 carried, and 1 injured for every 175,115 carried. Basing ratios upon the number of miles traveled, it appears that 55,211,440 passenger miles were accomplished for each passenger killed, and 4,385,309 passenger miles for each passenger injured.

 

Remains at Carnac, Brittany.—The name of Carnac in Brittany, the site of one of the most famous megalithic monuments in the world, is Breton for "the place of the cairn." As it IS described by Mr. T. Cato Worsfold, just outside the town is a tumulus twenty-five feet high, evidently artificial, and surmounted with a grove of trees. This mound was excavated a few years ago; the first remains come to were Roman; then, deeper down, Celtic pottery, etc, were found, and finally flint and granite arrowheads and celts, the finds reminding one of the hill of Hissarlik, with its layers of deposits. Close alongside the mound have been found the remains of a Roman villa, with hypocaust, etc., as usual, the owner of which, living about eighteen hundred years ago, must have been an archæologist, as some flint arrowheads, celts, and prehistoric pottery were found carefully placed on shelves in one of the rooms excavated. The megalithic monuments consist of numbers of great monoliths, from twelve feet to twenty-five feet in height, dolmens, or "table stones," great flat stones laid on a number of small menhirs and forming a chamber; and the alignments or rows—eleven in number and about two miles in length—of monoliths running from west to east, and terminating in a quaint chamber at the east end. The alignments—in three divisions, meaning severally the place of incineration, the place of mourning, and the place of the dead—consist of menhirs from two feet to twenty feet high, are sepulchral, and are evidently the work of the same race that built Avebury and Stonehenge, though data as to the time are wanting. Stonehenge is obviously the latest of the three, for the stones there are hewn out and fashioned with mortise blocks, etc., while Avebury and Carnac are rough and unhewn.

 

Coal-Mine Acids in the Schnylkill River.—It is shown in a paper by Prof. O. C. S. Carter that the Schuylkill River, above the city of Reading, is so strongly charged with sulphuric acid and sulphate of iron that it can not be used as a water supply, or, on account of its corroding boilers, for the generation of steam, and is very detrimental to fish, so that there are practically none in the river between Reading and Tamaqua. The acidity of the river is due to impurities found in coal. Before coal was mined in Pennsylvania the river, it is said, was free from acidity from its mouth to its source, and fish were found along its entire course. It is also said that the amount of acid in the Big Schuylkill from Pottsville and beyond has been decreasing since 1868, owing to the transfer of mining operations to the other side of the mountains, where the streams drain into the Susquehanna, and that the amount of sulphuric acid in the Big Schuylkill in 1885 was only one half of what it had formerly been. These statements can not be strictly verified for want of means of making comparative analyses, but are taken as true. Thanks to the decrease of acid, a few hardy catfish have found their way up to the region between Port Clinton and Pottsville, but no other fish; but even the catfish are not found in the river lower down, between Port Clinton and Reading, because of the discharge of acid waters by the Little Schuylkill at Port Clinton. The water loses its acid character in the vicinity of Reading, and neutralization is complete a short distance below. This is brought about by the pouring in of the hard, limestone waters of Maiden and Tulpehocken Creeks near Reading. At the mouths of these streams the sulphate of lime is precipitated by their action, rendering the water almost milky in appearance. In 1882, when a number of abandoned coal mines were opened and the excess of acid water was pumped into the river, there was more of it than the limestone streams could neutralize in the dry season; it passed far below the city of Reading, and hundreds of dead fish were observed floating in the river.

 

An Endless Source of Carbonic Acid.—Prof. E. W. Claypole's president's address at the last meeting of the American Microscopical Society—Microscopical Light in Geological Darkness—concerns the aid furnished by the microscope in geological study. Among the revelations afforded by means of this instrument is that which it has yielded, in the hands of Mr. H. C. Sorby, of Sheffield, England, of the existence of innumerable inclusions of liquid carbonic acid in the rocks. As investigation has gone on, the abundance of these bubbles has been more and more realized, and they are now found to be present "by myriads and by millions, and not in gems only, but in other crystalline minerals. In size they range between the one-thousandth and the fifty-thousandth of an inch, but they are so multitudinous as often to impart a white tint to the crystal, and many specimens of milky quartz owe their whiteness solely to the presence of these innumerable bubbles. In some of the Cornish granites the cavities make five per cent of the volume, and yield four pounds of the liquid to every ton of the rock." Mr. J. C. Ward is quoted as saying that more than a thousand millions of them might be contained easily within a cubic inch of quartz. The fact is used to cast light on the problem of the origin of the coal. Coal is derived from plants, which have extracted carbon from the carbonic acid of the atmosphere. Whence was that carbonic acid derived? It has been said that it was one of the original constituents of the atmosphere. But Professor Claypole adduces many reasons to show that all the carbonic acid represented in the coal beds could never have been in the atmosphere at one time. How, then, and whence, were the successive supplies introduced? Besides Mr. Sorby's experiments, those of Professor Tilden and others show that rocks of various kinds and in various localities yield gases, of which hydrogen and carbonic acid are the most abundant, in proportions ranging from 1.3 to 17.8 of the bulk of the rock, whence it may be inferred that these gases are occluded in most rocks. Now, immense volumes of the primary rocks have been worn away by the action of water, and have furnished the material from which the sedimentary rocks are derived. This washing away has involved the breaking open of the minute reservoirs of carbonic acid, and it has gone into the atmosphere, not all at once, but gradually, so as to furnish a continuous, not excessive supply. A brief calculation presented by Professor Claypole makes it evident that the rocks would thus furnish an abundant supply, and to spare, for all the coal that is known to exist.

 

The Houses of Saga Times.—The construction of the dwelling houses of Saga time—a. d. 875 to 1025—has been studied in Iceland by Dr. Valtyr Gudmundsson and Thorstein Erlingsson in co-operation with Miss Cornelia Horsford, by Lieutenant Daniel Brunn, and by the Icelandic Antiquarian Society; and in Greenland by the Danish Government. The ruins of the house believed to have been built by Erik the Red, in Hawk River Valley, Iceland, and in which Leif Eriksen was probably born, as well as the ruins of other similar houses, when undisturbed, are low, grass-grown ridges and hollows, often difficult to detect, except when stones protrude through the turf. A dwelling usually consisted of three apartments—a hall or principal room, in which there was always a fireplace; a sitting room for the women, and a storeroom or pantry. These apartments were like small houses, each with a separate roof, but attached to each other with passages through the thick walls. Near by were usually one or more outhouses. The dwellings were built on the surface of the ground; the floor was of finely beaten earth. The walls were about five feet thick, and somewhat higher. The inner side was built of unhewn stones, and the interstices were filled with earth. The outer side was of alternate layers of turf and stone, and the space between the two sides was filled in with earth kneaded hard. Often, however, the walls were built entirely of layers of turf or with only disconnected rows of stones at the base. A long, narrow fireplace usually extended through the middle of the room, and was either paved or surrounded with stones standing on edge. Besides the long fire, which served to warm and light the hall, there was a small cooking fire made in the same way. The Greenland houses resembled those of Iceland, but the walls were narrower, straighter, and stronger. The dwellings were usually long and narrow, consisting of from three to eight rooms, and were surrounded by outhouses and stables for cattle, sheep, and goats; and close to them are found enormous midden heaps. A ruin is described by Miss Horsford as existing near Cambridge, Mass., bearing marks of similar construction, and is attributed by her probably to Thorfinn Karlsefin's men; and another one, ten miles or more from the settlement at Cambridge, is supposed to be of later date. Very few relics were found in the Iceland houses, but more in those of Greenland—iron nails and knives, pieces of stone vessels, spinning stones, bone combs, and stone pendants bored with holes and incised with runelike but illegible characters.

 

Mr. Bandelier's Explorations.—The archæological researches of Mr. Adolphe F. Bandelier in Peru and Bolivia for about six years were prosecuted at first through the liberality of Mr. Henry Villard, but since 1894 under the auspices of the American Museum of Natural History. From a very cursory summary of his work given in the American Archæologist by F. W. Hodge, it appears that from almost the moment of his arrival at Lima he observed, even in the immediate vicinity of the city, a wealth of archaeological material. It was found, however, that the number of ruins was indicative of successive rather than contemporaneous occupancy. The detailed survey of the ruins proves that the cities they represent did not by any means harbor the numbers of inhabitants they have been usually believed to have contained. They were not compactly built cities, but included cultivated lots and fields occupying the greater proportion of the space. The buildings were of adobe and stone, with very thick walls. Artificial platforms and mounds are common, and tall mounds were found within the area of nearly every building examined. The aboriginal idioms have not entirely disappeared from among the natives of the Peruvian coast. Of ancient creeds and beliefs the practice of witchcraft seems to be the only vestige. Mr. Bandelier next reconnoitered the upper course of the Marañon River on the eastern slope of the Cordillera in the Peruvian north, whence the reports about the ruins of Kue-lap had created great interest. He passed the historically celebrated town of Cajamarca; traversed in the department of Amazonas an exceedingly broken and uneven country; and secured a complete plan of Kue-lap, with a number of details, furnishing data to correct previous accounts and surveys. He also gathered a number of traditions relative to occurrences anterior even to the time when the Incas began to make raids across the Marañon. After exploring many other ruins, the political conditions in Peru becoming unpleasant, Mr. Bandelier went into Bolivia, where he spent some time on the island of Titicaca, established the height of about 14,500 feet as the uppermost limit of sedentary occupancy in ancient times on the southern side of Illimani, and examined the slopes, up to 15,400 feet, of the great peak of Kaka-a-ka, or Huayna Potosi. At last accounts he was preparing for a journey to Pelechuco, in the northwestern corner of Bolivia.

 

Temperature Levels in Lake Mendota.—Prof. E, A. Birge, of the University of Wisconsin, has been pursuing studies of the "Plankton" of Lake Mendota in that State, with a prime view to making a contribution to the natural history of an inland lake as "a unit of environment." He finds that during the summer the difference in temperature between the surface and the bottom may amount to 10°, 12°, or even 15° C, but the decline in temperature from surface to bottom is not uniform as the depth decreases. If a series of temperatures is taken about the 1st of August it will be found that there is a layer of surface water from about twenty five to forty feet in thickness, the temperature of which is nearly uniform. Immediately below this mass of warm water lies a stratum in which the decline of temperature is extremely rapid. This stratum may be from about six to ten feet thick, with a decline of nearly as many degrees centigrade per yard; or it may be only about a yard thick. This layer in which the temperature decreases rapidly may be known as the thermocline—the Sprunsgchiet of German authors. Below the thermocline the temperature decreases toward the bottom at first more rapidly and then more slowly as the depth of water increases, but never showing the sudden transitions which are characteristic for the thermocline. The thermocline was first noticed by Richter in 1891 in a study of the Alpine lakes. Its origin was attributed by him to the alternate action of the sun warming the surface in the day, followed by a cooling at night. The alternation of the conditions resulted in the formation of a layer of water of nearly uniform temperature above the colder bottom water. In Lake Mendota the concurrence of gentle winds and hot weather is essential to the formation of the thermocline. The warmth of the surface water, received from the sun, is distributed through a certain depth of the lake, a depth which is proportional to the violence of the wind and the area of the lake. In a lake of the size of Mendota the water would be of uniform temperature from top to bottom if it were always agitated by violent winds. On the other hand, if the weather were perfectly calm, the lake would be warmed only to the depth to which the rays of the sun could directly penetrate.

 

Curious Photographic Effects.—Since the rise into prominence in 1895 of the X-ray phenomena, there has been a greatly increased interest among physicists in the even more curious but apparently closely allied phenomena of normal physical emanations from certain surfaces which have the property of influencing the sensitive plate, and in some cases even impressing an image on such insensitive substances as glass, copper, etc. These phenomena have been variously labeled scotography, vapography, etc, but there has not as yet been sufficient insight gained into their causes to allow of a truly descriptive title. Dr. W. J. Russell, who has made this phenomenon the subject of his last two Bakerian lectures before the Royal Society, is authority for the following statements. He had previously found that zinc, other metals, wood, straw-board, and printed papers, when placed in contact with a dry plate, had a certain action on it, which enabled it to be developed as if it had been exposed to light. In his later lecture he recounts a number of additional experiments. Zinc and other materials, when left in contact with the plate for a week, formed an image so exact that minute scratches were reproduced; the structure and rings of growth from the section of a pine tree, and even the grain of a piece of mahogany which had been in practical darkness for a couple of centuries, were transferred to the plate, with perfect fidelity. It was also found that actual contact was not necessary, the plate being affected through a considerable intervening air space, and through gelatin, gutta-percha tissue, collodion, and celluloid. Glass was found to be quite impervious. The emanations from certain uranium salts were found, however, to pass through the glass to some extent. Among the most active metals are zinc, magnesium, aluminum, nickel, lead, and bismuth. Copper and iron are practically inert. Strawboard and fresh charcoal and copal varnish act very strongly upon the plate. Pure mercury is inactive. For efficient and rapid action, a fairly high temperature (55° C.) and a perfectly clean metallic surface are necessary. Dr. Russell's views regarding the cause of this action are not definitely stated, but he seems to incline toward the theory that the effects are due to vapors given off by the objects.