Popular Science Monthly/Volume 5/July 1874/Miscellany
Volcanic Eruption in the Sandwich Islands.—A correspondent of the American Journal of Science writes that, until the past year, the great summit crater of Mauna Loa (Sandwich Islands) has for a number of years shown but few and feeble symptoms of activity. For a few days in August, 1872, there was a brilliant light in the crater, and again on the 6th and 7th of January, 1873, there were vivid demonstrations, which roused the attention of many witnesses. But it was not until the 20th of April, 1873, that a continuous exhibition of mountain pyrotechnics commenced. From that day down to the date of the letter (January 6, 1874), the action within the great caldron was incessant. Most of the time the boiling was vehement. "The scene was never more brilliant than a few nights ago. Sustained jets of molten rock were constantly rising 50 to 200 feet within the mural caldron, and the surgings, puffings, and roarings, have been heard low down the sides of the mountain, and, as some testify, as far as Reed's Ranch, probably fifteen miles." The most distinguishing feature of this eruption, however, was its duration. The eruption of 1855-'56 flowed fifteen months; but this rent the mountain laterally, and flowed longitudinally; whereas the present eruption has made no lateral vent, and found no outlet, so far as known. During all this time Kilauea was unequally active. The great depression of Kilauea, caused by the eruption of 1868, is fast filling up by repeated over-flows from the south lake, while all around that lake a vast mound is rising, whose summit is nearly as high as the southern rim of Kilauea, and it may soon over-look it.
Need of a New Chronology.—From the presence of the Egyptian Pyramids, Bayard Taylor thus writes to the New York Tribune: "As I rested in the shade, looking up to the gray pinnacles, so foreshortened by nearness that much of their actual height was lost, yet still indescribably huge, I could think of but one thing: we must have a new Chronology of Man. There, before me, the Usher-Mosaic reckoning was not only antedated, but a previous growth, of long, uncertain duration, was made evident. There, in stones scattered about the Desert, were inscriptions cut long before any tradition of Hebrew, Sanscrit, Phœnician, or Greek—clear, intelligible words, almost as legible to modern scholarship as those of living languages. This one long, unbroken stream of light into the remote Past lights up darker historic apparitions on all sides, and sweeps us, with or without our will, to a new and wonderful backward starting-point. Of course, the learned in all countries are familiar with all our recently acquired knowledge on this point; but is it not time to make it the property of the people everywhere—to discard the unmanly fear that one form of truth can ever harm any other form to reveal anew, through the grandeur of Man's slow development, the unspeakable grandeur of the Divine Soul by which it is directed?"
Life in an Attenuated Atmosphere.—M. Paul Bert, in a communication to the French Academy, details some further experiments made on himself, with reference to the effect of changes of barometric pressure on life. He entered his large apparatus of decompression, and the pressure was brought down to 450 millimetres (somewhat less than 18 inches of mercury); it was then maintained between this and 408 millimetres (16½ inches) for a little over an hour. These pressures correspond to heights of 13,448 and 16,728 feet. At 450 millimetres the author began to experience "mountain sickness"—a feeling of heaviness and weakness, nausea, fatigue of sight, general indifference, and laziness. Having lifted his right leg, it was thrown into convulsive trembling, which extended to the left, and lasted some minutes. The face was somewhat congested, and the temperature under the tongue increased. He also remarks that he was unable to whistle. The important point of these experiments, however, was this: he had taken with him a small vessel full of oxygen, and, when the pressure had reached 430 millimetres, he inhaled some of it. His pulse, which had risen from 62 to 84, immediately fell to 71, and the mountain-sickness for a time disappeared. Immediately on inhaling the oxygen there was a disagreeable dazzling, and at one time, after three inspirations, he became giddy and fell off his chair, but soon recovered. The author also describes the effects on himself of breathing a super-oxygenated mixture. With a mixture of 45 per cent., he could bear without injury a pressure of only 338 millimetres, which corresponds to the height of Chimborazo; and with 63 per cent. he was able to stand 250 millimetres (less than ten inches), and would have gone farther if his machine had been sufficiently strong. Since M. Bert's experiments, Messrs. Croce-Spinelli and Sivel have made a balloon-ascension to the extraordinary height of about 26,000 feet. They carried up with them a supply of oxygen, and, by using this after the manner indicated by M. Bert, they were enabled to live without inconvenience in an atmosphere of extreme rarity.
Lake Superior Gold-Mines.—Mr. Peter McKellar lately read, at the Toronto Institute, a paper on the gold-mines of Lake Superior. Some Indians from the vicinity of Thunder Bay, in 1871, brought to Mr. McKellar, at Fort William, several specimens of quartz, from an examination of which he was led to think that valuable gold-mines existed in the locality. The paper then described the lodes that had been discovered. The first was the Jackfish Lake lode, which lies about eighty miles west of Thunder Bay. From this lode 126 pounds of ore were sent to the Wyandott Smelting-Works, and yielded at the rate of $500 per ton; of this sum, $40 was derived from silver, and the remainder from gold. The Partridge Lake lode, lying about 100 miles northwest of Thunder Bay, yielded about $30 per ton of ore. In the summer of 1872 another lode, called the Heron Bay lode, was discovered, about 150 miles northeast of Fort William. It was similar to the Jackfish Lake lode, excepting that its yield of gold and silver was not so great. Mr. McKellar holds that these mines might be worked very economically, and that they would yield as large profit as, if not larger than, any others in the world. In the lodes already discovered, the gold was found very evenly distributed through the ore, which is said to exist in large quantities. Iron, lead, and other metals, occur in the neighborhood. The difficulties in developing these mines have been very great, owing principally to the unsettled state of the country. The Indians have refused to help in working the mines until some settlement shall be come to with them, as they fear that white men may come and dispossess them.
Researches on the Zodiacal Light.—Prof. Arthur W. Wright, of Yale College, who for upward of a year has been closely investigating the zodiacal light, has, by means of an apparatus of his own contriving, succeeded in demonstrating that this light is polarized. In the American Journal of Science, for May, Prof. Wright describes his polariscope, and the results at which he has arrived in the course of his researches. He finds that the plane of polarization of the zodiacal light passes through the sun. In no instance, when the sky was clear enough to render the bands visible, did their position, as determined by the observations, fail to agree with what would be required by polarization in a plane through the sun; not the slightest trace of bands was ever seen when the instrument was directed to other portions of the sky.
Having thus determined the fact of polarization, the next step was to ascertain what percentage of the light is polarized. For this purpose, the author again had to devise novel apparatus. The amount of polarization was determined to be, "with a high degree of probability, as much as 15 per cent., but can hardly be as much as 20 per cent."
The fact of polarization implies that the light is reflected, either wholly or m part, and is thus derived originally from the sun. The spectrum of the zodiacal light is not perceptibly different from that of sunlight, except in intensity. The author adds: "A particular object in these observations was to determine whether any bright lines or bands were present in the spectrum, or whether there is any connection between the zodiacal light and the polar aurora." The results give a decidedly negative answer to this question. "This is important here," says the author, "as excluding from the possible causes of the light the luminosity of gaseous matter, either spontaneous, or due to electrical discharge. The supposition that the light is reflected from masses of gas, or from globules of precipitated vapor, is not to be entertained, since, as Zöllner has shown, such globules in otherwise empty space must evaporate completely, and a gaseous mass would expand until its density became far too small to exert any visible effect upon the rays of light."
From this it follows that the light must be reflected from matter in the solid state, that is, from innumerable small bodies (meteoroids) revolving about the sun in orbits crowded together toward the ecliptic.
The Great Lava-Flood of the West.—Prof. Joseph Le Conte, of the University of California, visited, during the summer of 1873, the central and eastern portions of Oregon, a vast lava-covered region, and published the results of his observations in the American Journal of Science for March and April, 1874. Using the word lava as synonymous with eruptive rocks, he says that between 200,000 and 300,000 square miles of surface is one field of lava. It is probably the most extraordinary lava-flood in the world. Commencing in Middle California as separate streams, in Northern California it becomes a flood flowing over and completely mantling the smaller inequalities, and flowing around the greater inequalities of surface; while in Northern Oregon and Washington it becomes an absolutely universal flood, beneath which the whole original face of the country, with its hills and dales, mountains and valleys, lies buried several thousand feet. It covers the greater portion of Northern California and Northwestern Nevada, nearly the whole of Oregon, Washington, and Idaho, and runs far into Montana on the east, and British Columbia on the north.
This enormous mass of matter evidently arose through fissures, and flowed until the streams or masses met, forming an almost continuous sheet. The Cascade Range of mountains seems to have been a source of immense overflow.
The area covered by this overflow cannot be less, says Prof. Le Conte, than 100,000 square miles, with an average thickness of about 2,000 feet, but having a thickness in some places of 3,700 feet. The statement, which seems an extraordinary one, is sustained by the extensive observations of Prof. Le Conte. The Columbia River cuts through the Cascade Range in a gorge a hundred miles in length, with perpendicular cliffs. The cascades of the river are at the axis of the range, and the cliff's here are 2,500 to 3,800 feet above the river-surface, and are composed of lava, tier upon tier, from top to bottom. Considering surface erosion, 4,000 feet is regarded as a moderate estimate for the original thickness of the lava-flood at this place.
But the entire thickness of the lava has been cut through, and the surface revealed on which the flood was originally formed. Here, at the river's surface, underlying the mountains of lava, are remains of ancient forests, and evidences of interesting geological changes.
There occurs at the river's edge, and about fifteen feet upward, a layer of coarse conglomerate; on this, a layer which appears to have been a dirt-bed, or old-ground surface. On this surface were found two silicified stumps, with their roots spread out, one of which was two feet in diameter, the roots reaching over an area twenty feet in diameter. Trunks of other trees were seen. Over this was a layer of stratified sandstone, with beautiful impressions of leaves of several kinds of forest trees. Upon this lies about 100 feet of conglomerate, resembling drift, in the bottom of which were found trunks and branches of oaks and conifers. Upon the conglomerate the lava lies in columnar masses to a height of 3,300 feet.
The geological age of the wood and leaf-bearing stratum is believed to be miocene, or middle tertiary, and, if so, the lava-flood began to occur during or after the miocene.
Why Paints crack and peel.—A writer in The Hub thinks that the cause of paint cracking and peeling is to be found in the water which is contained in linseed-oil, as it comes from the hands of the manufacturer. He made the experiment of boiling linseed-oil by the heat of steam, until all the moisture was expelled from it. On using this oil, without any drier, it was found to dry in one-half the usual time. He then mixed with it some siccohast, using only half the usual quantity employed to dry oil not boiled, and obtained similar results. "The introduction," says he, "of steam into the linseed before grinding aids in the expulsion of the oil; but it must stand a long time to precipitate the water completely. Boiling oil by steam does not change its complexion, save that it renders it clearer, and less liable to turn yellow with white pigments."
Results of the Polaris Voyage.—The following is from Dr. Bessel's memoranda of the discoveries of the expedition:
1. The Polaris reached 82° 16' north, a higher latitude than has been attained by any other ship. Captain Buddington's testimony is very definite as to the impracticability of pushing a vessel farther north than the point which they reached.
2. The navigability of Kennedy Channel has been proved beyond a doubt.
3. Upward of 700 miles of coast-line have been discovered and surveyed.
4. The insularity of Greenland has been proved.
5. Numerous observations have been made relating to astronomy, magnetism, force of gravity, ocean physics, meteorology, zoology, ethnology, botany, and geology, the records of which were kept in accordance with the instructions supplied by the National Academy. A ninety-fathom sounding along the coast of-and brought up a highly-interesting organism of lower type than the Bathybius discovered by the English Dredging Expedition. It was named Protobathybius Robesonii. The natural-history collections were nearly all lost. They consisted of mammals, nine species of fur-bearing seals; birds, twenty-one species; insects, about fifteen species, viz., one beetle, four butterflies, six diptera, one bumble-bee, and several ichneumon-flies; also two species of spiders, and several mites.
It was found that the land was rising. Garnets of unusual size were found in latitude 80° 30', having marked mineralogical characteristics by which the identity of some garnets from Fiskenaes was established. From such observations it became evident that the drift, which abounded on the land, runs from south to north.
Australian Compliment to American Microscopes.—But a short time ago, a small number of microscopists met in Melbourne, and decided to form an organization under the name "Microscopical Society of Victoria, New South Wales." The first general meeting of the Society was held in the Royal Society's Hall, October 10, 1873. About forty gentlemen were present, and a good exhibition of instruments and work was made. The president, Mr. W. H. Archer, read an address, from which we extract the following significant passage. Geologically, it is the oldest continent speaking to one the next in age; although politically it is the most recent of the peoples, speaking of science among one but a little older than themselves:
"One of the most interesting and practically useful objects for occasional investigation and discussion at our meetings will be the accurate determination of the real value to working microscopists of the various stands, objectives, and accessory apparatus so prodigally developed by makers in the mother-country. But, indeed, we should not confine ourselves to the results of English industry. Hartnack, of Paris, appears to be leading the way on the Continent to greatly-improved optical work; and Tolles, Spencer, and Wales, are said to be doing marvels in America. I hope to see the day when we shall have choice proofs of what the whole microscopical world can produce collected around us, and carefully tested by our own eyes and hands, in our own hall in Melbourne. One other thing, gentlemen, you as well as I should be rejoiced to see, and that is a really useful microscope of Victorian manufacture. At present, the idea is naturally provocative of a smile, but I cling to the belief that not only among the adult immigrant population, but even among our native-born youth, we shall some day find thorough mechanicians, who will emulate the marvelous skill and persistent energy of their forefathers. Look at the triumphs of the American microscope-makers. Their conquests are literally tut of yesterday and of to-day. A generation ago microscopes were a rarity in America. In the year 1840, when the United States Exploring Expedition to the South Seas, under Commander Wilkes, was fitting out, it was thought necessary to have a microscope. The various makers of scientific and philosophic instruments were applied to, but none of them could furnish the expedition with the thing desired. In this dilemma a private individual was appealed to, and an instrument thus finally obtained, in the shape of an inferior French microscope. How, then, did the present flourishing state of affairs come about? Simply by the genius of a self-taught man. He was a backwoodsman, and had pored over an old cyclopædia, and turned the optical knowledge contained therein, as far as in him lay, to sound practical account. At the age of twelve years he made his first lens. One day he happened to be shown a microscope constructed by Chevalier, of Paris, and the thought struck him that he would try to make a similar instrument. He succeeded, and his glasses were able to resolve a test which similar objectives of the first English opticians had hitherto failed to define. His name was Charles Spencer. And now his pupil Tolles, and Wales, a pupil of Smith and Beck, with Gronow, Zentmayer, and others, form a galaxy of American mathematical instrument talent that appears from recent accounts to be holding its own against the whole of the world. Is there not here a ground for the hope I expressed a little while ago? Surely after this example of Spencer, the young backwoodsman, many here present may live to see the day when a finished microscope shall be presented to their delighted gaze by the hands of an Australian townsman, at least, if not by an Australian bushman."
The Improvement of Human Life.—An extremely valuable paper by Dr. Edward Jarvis, on "Political Economy of Health," published in the Fifth Annual Report of the Massachusetts Board of Health, groups together very strikingly the vital statistics of various countries, to show the effect of the advance of civilization in protracting the term of human life. By better adaptation of means, circumstances, and habits, says Dr. Jarvis, man's life has been expanded, his strength increased, and his days on earth prolonged. By the improvements in agriculture and in vegetable and animal life, he has obtained better and more constant food, and is therefore better nourished. By the improvements in the arts he is better clothed and housed, better protected from the elements. The progress of civilization is best manifested in the progress of vitality. There is less sickness, and that which visits humanity is less destructive than in former ages.
In ancient Rome, in the period 200 to 500 years after the Christian era, the average duration of life in the most favored class was 30 years. In the present century the average longevity of persons of the same class is 50 years. In the sixteenth century the average longevity in Geneva was 21.21 years; between 1814 and 1833 it was 40.68, and as large a proportion now live to 70 as lived to 43 three hundred years ago. In 1693 the British Government borrowed money by selling annuities on lives from infancy upward, on the basis of the average longevity. The treasury received the price and paid the annuities regularly as long as the annuitants lived. The contract was mutually satisfactory and profitable. Ninety-seven years later Mr. Pitt issued another tontine or scale of annuities, on the basis of the same expectation of life as in the previous century. These latter annuitants, however, lived so much longer than their predecessors, that it proved to be a very costly loan for the Government. It was found that while 10,000 of each sex in the first tontine died under the age of 28, only 5,772 males, and 6,416 females in the second tontine died at the same age one hundred years later. The average life of the annuitants of 1693 was 26.5 years, while those of 1790 lived 33 years and 9 months after they were 30 years old.
From these facts, says Dr. Jarvis, it is plain that life, in many forms and manifestations, and probably in all, can be expanded in vigor, intensity, and duration, under favorable influences. For this purpose it is only necessary that the circumstances amid which, and the conditions in which, any form of life is placed, should be brought into harmony with the law appointed for its being. By this means the intelligent world has been and is now continually adding to the vitality of the vegetable and animal kingdom, as far as they are brought under their control. Man has increased his own life also, in so far as he has conformed his self-management to the requirements of the vital law.
Fossil Edentates.—Prof. O. C. Marsh, in the current number of the American Journal of Science, describes some new fossil mammals, being edentates of a stupendous size. They go back very much farther, geologically, than any American species previously described. Some of them are from the Upper Eocene of Wyoming Territory.