Popular Science Monthly/Volume 7/September 1875/Miscellany
TO HERBERT SPENCER.
BY GRANT ALLEN.
Deepest and mightiest of our later seers,
Spencer, whose piercing glance descried afar
Sleep and Digestion.—Speaking from his own experience, which would appear to differ from the experience of other people, Frank Buckland asserts that the best time to go to bed is immediately, or very soon, after the principal meal of the day. "All animals," he remarks, "always go to sleep, if they are not disturbed, after eating. This is especially noticeable in dogs; and the great John Hunter showed by an experiment that digestion goes on during sleep more than when an animal is awake and going about." Mr. Buckland finds a confirmation of his theory in the drowsiness which settles down on elderly men over their wine. "Nature says to them, 'Go to bed.' They will not go to bed, but still Nature will not allow her law to be broken, so she sends them to sleep sitting in their chairs." But, then, does not Nature quite as clearly indicate, by means of the nightmares and the unrest with which she torments the would-be sleeper who has gone to bed directly after a heavy meal, that a full stomach is not the best preparation for slumber? Many persons with whom this prescription for sleep would fail, may perhaps find another prescription given by Mr. Buckland more effectual, viz., eating onions, the essential oil of which possesses highly-soporific powers.
The Use of Paris-Green.—The use of Paris-green in dealing with the Colorado beetle has been condemned on the ground both that it poisons the soil, rendering it sterile, and that it is liable to be absorbed by the plant. Certain experiments made by Mr. McMurtrie, chemist of the Department of Agriculture, throw much light upon this question, and therefore are worthy of reproduction here. To determine the first point, that is, whether the Paris-green poisons the soil, Mr. McMurtrie planted peas in a number of flower-pots, each containing the same amount of earth, and all but one containing a certain proportion of Paris-green. The proportion of this substance varied from 100 milligrammes up to five grammes. The first five pots contained Paris-green as follows: No. 1, none; No. 2, 100 milligr.; No. 3, 200; No. 4, 300; No. 5, 400. In all of these the peas grew equally. In No. 6, containing 500 milligrammes, the plant was less vigorous than in No. 5. This, then, may be regarded as the proportion of Paris-green which impairs the fertility of soil. As the proportion increases, the plant grows feebler and feebler till No. 12 is reached, containing two grammes of Paris-green. Here the plant barely appears above the surface. In the rest of the pots, containing respectively three, four, and five grammes, the plant sends no shoot above the surface.
The proportion of 500 milligrammes in the flower-pot No. 6 is equal to 145.6 grammes per cubic foot, or 906.4 pounds per acre, I calculating for a depth of one foot. Now, as less than two lbs. of Paris-green per acre is enough to use in warring against the beetle, it would take about 500 years to poison the soil, supposing the green to be applied every year, and that it was all retained. "But when rotation of crops is practised," says Mr. McMurtrie, "and application of the poison cannot therefore take place upon the same plot more than once in three or four years, it is probable that each application, being acted on by the natural solvents of the soil, will be removed by drainage before another is made." To the question whether arsenic can be absorbed and assimilated by the plant in the economy of growth, he replies in the negative. All of the plants grown, from the largest to the smallest, were examined according to Marsh's test for arsenic, but its presence could not be detected.
Periodicity of Thunder-storms.—W. von Bezold lately presented to the Munich Academy of Science a paper on the "Periodicity of Thunder-storms," basing his remarks upon a series of observations which extended over a period of 105 years prior to 1869. A synopsis of this paper we here reproduce from the American Journal of Science. He finds that in years when the temperature is high and the sun's surface relatively free from spots, thunder-storms are abundant. But as the maxima of the sun-spots coincide with the greatest intensity of auroral displays, it follows that both groups of phenomena, thunder-storms and auroras, to a certain extent supplement each other, so that years of frequent storms correspond to these auroras, and vice versa. He observes that such a connection between sun-spots and storms does not by any means sanction the supposition of a direct electrical interaction between the earth and the sun, but may be simply a consequence of a degree of insolation dependent upon the sun-spots.
These changes in the insolation, according to Köppen, manifest themselves in different latitudes not contemporaneously but successively. The phenomena of thunderstorms, on the other hand, do not depend alone upon the condition of the place in question with respect to temperature, but also on the condition of the atmosphere at points far distant and belonging to another zone. This appears most distinctly in the storms which accompany electrical displays. The peculiar intermediate position which the weather curve takes between the curves of sun-spots and temperature may possibly find its explanation in this fact. Observations recently published in Saxony confirm these conclusions in a striking manner.
Volcanic Outbreaks in Iceland.—Since the beginning of the present year volcanic action has been almost incessant in Iceland. The following particulars of the outbreaks we find in Nature: In March the Dyngjufjöll was incessantly vomiting fire, and the eruption was steadily spreading over the wilderness. The farmers in the region around the My-vatn Mountains were obliged to remove in order to find pasture for their stock, the country being covered with ashes. Early in April a new eruption had broken out in a southeasterly direction from Barfell. A party went out from Laxardal to explore, and on approaching the place of eruption they found the fire rising up from three lava-craters. At a distance of 100 to 150 yards to the west from the craters a large fissure had formed itself as the fire broke out, and the land had sunk in to the depth of about 18 feet. Into the hollow thus formed the lava had poured at first, but now it flowed in a southwest direction from the two southern craters. The northernmost crater had the appearance of being oblong, about 600 yards in length, and from this crater the molten red-hot lava was thrown about 200 or 300 feet into the air in one compact column. The top of this column then assumed a palmated appearance, and the lava fell down in small particles, like drops from a jet of water, which, as they became separated from the column, grew gradually darker, and split into many pieces, bursting into lesser and lesser fragments as they cooled. No flames were observed, but the glare proceeded from these columns and the seething lava in the craters. At times the explorers could count twenty to thirty of these columns. No real smoke accompanied the eruption, but a bluish stream, which expanded and whitened in color as it rose to a greater distance from the crater; and such seemed to be the power of this blue jet of steam that it rose straight into the air for many thousand feet, despite a heavy wind blowing.
How we keep our Mouths shut.—Bonders asserts that the mouth is kept closed, not by the action of the muscles connected with the lower jaw, but by atmospheric pressure. He has investigated this phenomenon experimentally. By employing a manometer, communicating with the space between the tongue and the hard palate, he finds, when the mouth is kept shut, a negative pressure corresponding to from two to four millimetres of the mercurial column. There are two suctorial spaces in the mouth: the principal one is bounded by the tongue below, the hard palate above, and the soft palate behind; the other is situated between the tongue and the floor of the mouth. The former is used in sucking liquid through a straw; the latter (sometimes) in smoking. Both are employed when we endeavor, with the mouth closed, to extract a foreign body from between the teeth. The mouth may be shut during sleep, when the muscles of mastication are relaxed. If a man fall asleep in the sitting posture with his mouth open, his jaw drops; the tongue not being in contact with the hard palate, the suctorial space is obliterated; the soft palate no longer adheres to the root of the tongue; and, if respiration be carried on through the mouth, the muscular curtain begins to vibrate, and snoring is the result.
Allaskan and Alëutian Mummies.—The custom of preserving or mummifying the bodies of the dead, as formerly practised by the natives of the islands in Behring Sea, is accounted for very ingeniously by Mr. William H. Ball, in the American Naturalist. On the main-land, either on the Asiatic or the American side, the custom does not appear ever to have existed. In the Chukchee Peninsula, on the Asiatic side, there is no soil in which to bury the dead, and cremation is impossible from the want of wood; hence the natives expose their dead to the tender mercies of bears, dogs, and foxes. In the Yukon Valley, Alaska, the soil is frozen hard, and excavation is extremely difficult; but timber abounds, and the bodies of the dead are boxed up in wooden coffins and elevated on four posts. On the islands the soil is not permanently frozen, and graves might be easily dug, but wood is scarce. Here the bodies might easily be buried, were it desirable. But, then, why bury the dead, if there are no wild animals to disturb the remains? The islands have no such animals, and hence the natives laid their dead away in nooks and crannies of the rocks.
Mr. Dall describes as follows the method adopted by the Kaniags and Alëuts in preserving dead bodies: First, an opening was made in the pelvic region, and the internal organs removed. The cavity was then filled with dry grass, and the body placed in running water. This in a short time removed most of the fatty portions, leaving only the skin, bones, and muscles. The knees were then brought up to the chin, and the whole body secured as compactly as possible by cords. The bones of the arms were sometimes broken to facilitate the process of compression. The remains were then dried. When thoroughly dried, the cords were removed, and the body usually wrapped in a shirt made of the skin of aquatic birds, with the feathers on; over this were wrapped pieces of matting, varying from coarse to exceedingly fine. Over this sometimes a water-proof material, made from the split intestines of the sea-lion, sewed together, was placed. Outside of this were usually the skins of the sea-otter, or other fur-animals, and the whole was secured in a case of seal-skins, coarse matting, or similar material, secured firmly by cords, and so arranged as to be capable of suspension.
Age of the Niagara Gorge.—It has for thirty years been the received opinion of geologists that the whole of the gorge of the Niagara, from Queenstown to the Falls, was excavated since the glacial period, and the work here done has been assumed to be a more or less accurate measure of the time elapsed since that period. But Mr, Thomas Belt, on a visit to Niagara last year, discovered what he takes to be sufficient evidence for asserting that the post glacial gorge extends only from Queenstown up to the whirlpool, and that between the latter point and the Falls the Niagara flows in its preglacial bed. The author holds that the present river is cutting back the gorge much more slowly than Lyell estimated; that, instead of one foot yearly, the retrocession is not more than, if it is as much as, one foot in ten years; and that, allowing for the comparative softness of the rocks below the whirlpool, we must put back the occurrence of the glacial period to at least 200,000 years ago, supposing the entire gorge from Queenstown to the Falls to have been excavated since that time. "But if," says Mr. Belt, "the conclusion at which I have arrived is correct that the gorge, from the whirlpool to the Falls, is preglacial, and that the present river has only cut through the softer beds between Queenstown and the whirlpool, and above the latter point merely cleared out the preglacial gorge in the harder rocks—then 20,000 years, or even less, is amply sufficient for the work done, and the occurrence of the glacial epoch, as so measured, will be brought within the shorter period that, from other considerations I have argued, has elapsed since it was at its height."
Have Animals a Sense of Humor?—A writer in Nature, George J. Romanes, brings together some instances tending to show the existence in some animals of a sense of humor. A young orang-outang in the London Zoölogical Gardens used frequently to amuse the spectators by inverting on her head her feeding-tin, and the animal was evidently gratified when her conduct called forth a laugh. A Skye terrier belonging to Mr. Romanes, "while lying upon one side and violently grinning, would hold one leg in his mouth." The animal was much pleased whenever this "joke" was duly appreciated, but would become sulky if no notice was taken of it. This dog was fond of catching flies upon the window-panes; but, if ridiculed when unsuccessful, he was evidently much annoyed. Having failed repeatedly on a certain occasion to catch a fly, he eventually became so distressed that "he positively pretended to catch the fly, going through all the appropriate actions with lips and tongue, and afterward rubbing the ground with his neck as if to kill the victim. So well," continues Mr. Romanes, "was the whole process simulated, that I should have been quite deceived, had I not seen that the fly was still upon the window. Accordingly I drew his attention to this fact, as well as to the absence of any thing upon the floor; and, when he saw that his hypocrisy had been detected, he slunk away under some furniture, evidently very much ashamed of himself."
Mechanical Action of Light.—It has been supposed that the rays of light, as distinguished from heat-rays, can produce no mechanical effects, such as repulsion and attraction; and the circumstance that these rays are unable to propel the arms of a vane suspended in vacuo has even been employed as an argument against the truth of Newton's emission theory of light. Mr. William Crookes, however, at a recent meeting of the London Royal Society, exhibited an apparatus which he calls "the radiometer," by means of which he proves that the luminous rays produce direct mechanical effects, after all the thermic rays have been strained out. The radiometer is described as consisting of four pith disks, fixed at the extremities of two crossed arms of straw balanced on a pivot at the point where the straws cross each other, so that they can spin round on the pivot. These pith disks are white on one of their sides and blackened on the other. The entire arrangement is inclosed in a glass bulb, from which the air is removed by means of a Sprengel pump. On being subjected to the action of light from which ninety-five per cent, of the heating rays had been strained out by means of an interposed plate of alum, the disks rotated with a speed little inferior to that when the heat-rays were allowed to mingle with the rays of light. And what is very singular, it is the blackened surface which is repelled by the luminous rays. Inasmuch as light is reflected by a white surface, and absorbed by a black, one should expect that in the experiment the white faces of the disks would rather be repelled. This anomaly Mr. Crookes does not attempt to account for, and he is content to let the facts speak for themselves, being confident that in due time the laws governing them will be made manifest.
It having been suggested by Prof. Osborne Reynolds that the movement of the little vane might be due to evaporation and condensation on the surface of the pith disks, Mr. Crookes showed that this was not the case He exhibited the very same effects with a lever-arm of platinum, suspended by an arm of platinum, the whole of which had been heated to redness again and again, during thirty-six hours of exhaustion by the Sprengel pump.
Prof. Huxley on the Amphioxus.—In a preliminary note upon the brain and skull of Araphioxus (the lancelet), Prof. Huxley shows that, although these organs are not fully differentiated in this animal, yet well-marked divisions of the nervous axis and spinal column exist which answer to the encephalon and cranium of the higher fishes. The homologies of the anterior pairs of nerves are worked out, and the skull is considered to be represented by the segments of the body which lie in front of the fifteenth, counting from before backward. The many points of resemblance in structure between the lancelet and the young form or larva of the lamprey (petromyzon) are insisted on, and it is suggested that Amphioxus should be regarded as the type of a new primary division of the class Pisces, to be called Entomocrania, as contrasted with all other known fishes, in which the primary cranial segmentation is lost, and for which the term Holocrania is proposed.
What Savages think of Twins.—In Africa, according to Dr. Robert Brown ("Races of Mankind"), the birth of twins is commonly regarded as an evil omen. No one, except the twins themselves and their nearest relatives, is allowed to enter the hut in which they first saw the light. The children are not allowed to play with other children, and even the utensils of the hut are not permitted to be used by any one else. The mother is not allowed to talk to any one not belonging to her own family. If the children both live till the end of the sixth year, it is supposed that Nature has accommodated herself to their existence, and they are thenceforth admitted to association with their fellows. Nor is this abomination of twin births restricted to Africa. In the island of Bali, near Java, a woman who is so unfortunate as to bear twins is obliged, along with her husband, to live for a month at the sea-shore or among the tombs, until she is purified. The Khasias of Hindostan consider that to have twins assimilates the mother to the lower animals, and one of them is frequently put to death. An exactly similar belief prevails among some of the native tribes of Vancouver Island, Among the Ainos, one of the twins is always killed, and in Arebo, in Guinea, both the twins and the mother are put to death.
Father Secchi on Solar Spots.—In summing up the results of his observations on solar prominences and spots from April, 1871, the Roman astronomer, Father Secchi, states that since that date there has been a very marked diminution both in the number of groups of sun-spots and in their area—a result of the eleven-year period, the maximum having occurred about 1871. But he has observed the same diminution in the number of prominences: in 1871 the daily average was about fifteen, while now it is six or seven. In the same period the number of groups of sun-spots in each rotation has decreased from about twenty-five to eight, and the mean area has diminished to about one-fifth. Further, the prominences are now very rare near the poles. Secchi further remarks on the discordance between his results of 1852, showing a difference of temperature between the solar equator and poles, and those of Prof. Langley, and infers that there has been a change in the sun in this respect, consequent on the decrease of solar activity. He objects to Langley's method of moving his thermopile to different parts of the image instead of moving the telescope so as to bring the points of the image in succession on the thermopile, and thus to avoid differences of inclination to the axis of the lenses.
Prof. Loomis on the Storms of the United States.—This eminent meteorologist presents, in the July number of the American Journal of Science, his third paper on storms, founded on the weather-maps of the Signal-Service. He is now able to confirm what was stated in his previous papers in regard to the general progress, direction, and barometric phenomena of storms in the United States. These papers of Prof Loomis are admirable in method, and of very great value. The general direction of the storms which traverse the United States is found to be a little north of east, but varies somewhat with the seasons. Thus, July storms are most southerly in their direction, being a little south of east, those of February being most northerly. Rarely, storms move for a time northward or southward.
By direction of a storm is meant the movement over the country of the whole storm, not the direction of the winds, and its progress varies greatly in rapidity. The average velocity during the past three years has been 26 miles per hour, the storms of August being slowest, those of February and March being most rapid. The storm of February 22, 1874, moved at the tremendous rate of 53.3 miles an hour, or 1,280 miles in a day.
It is also shown that the progress of storms is not uniform throughout the day, but has a uniform daily variation. The velocity is greater by 25 per cent, from 4.35 p. m. to 11 p. m. than during other portions of the day, and this is constant during each month of the year. The greatest velocity occurs at about 7 p. m. without apparent relation to the wind's velocity, or absolute temperature. "But," the professor observes, "it is the time when the temperature of the day is declining most rapidly." Now, this change of temperature has direct relation to those conditions which cause precipitation and extend the rain-area. By reference to a former paper of Prof. Loomis it will be seen that condensation in front of the storm-centre is one means by which a storm progresses. It is continually making up in its front where the air is vapor-laden, not in its rear where the air has been deprived of its vapor.
It will hardly admit of question that the velocity of a storm's forward motion is usually accompanied by an extension of the rain area in the direction in which the storm progresses. The average extent of this area in front of the storm-centre during three years is found to be 542 miles. Now, if this be increased 100 miles, the velocity of the storm is also increased, and the reverse occurs when the area is diminished.
The general outline of a storm-area is an oval, the longest diameter of which is in direction of the storm's progress.
Around the centre of a storm are points or lines of equal barometric pressure, and the lines thus formed are called isobaric curves. These are, in shape, irregular oval, and the longer diameter may be, or may not be, in the direction of the storm's longer axis. The prevalent direction is a little north of northeast.
Prof. Loomis suggested in a former paper that intense and sudden cold arises from vertical movement or displacement of air, by which the warm air suddenly, in some cases almost instantly, rises, the cold air of the upper atmosphere displacing it by its descent. This conclusion is confirmed by recent observations. On the 15th of January, 1875, the thermometer at Denver indicated a fall of temperature of 48° in one hour, and, in another instance cited, the change was 36° in five minutes! It is significant that these sudden invasions of cold air appear first, as a rule, on the Rocky Mountains, or contiguous highlands. The presence of mountains seems to favor the development of cold, which would not be the case if the movement of the cold wave was an horizontal one from the arctic regions, as formerly supposed.
Experiments on the Sense of Taste.—In a communication to the London Physical Society on subjective sensations of taste, Dr. Stone called attention to two simple experiments, the first of which consists in applying a strong dilution of nitric acid to the root of the tongue by sucking it through a fine glass tube. If pure water be swallowed immediately after this, a sweet taste is produced. The author compared this effect to the complementary images seen in the eye after gazing at a powerfully illuminated body. He then adverted to the taste of the galvanic current. In the well-known experiment with pieces of zinc and silver, the zinc is actually dissolved in the saliva. But if one pole of a strong battery (ten Grove's cells in this case) be applied to the nape of the neck, and the other brought to the forehead, besides the flash of light, a strong taste is experienced of a metallic character. It disappears on breaking contact; and for this reason, as well as from the fact that the tongue is not in the direct line of circuit, and also that there is no substance in the saliva likely by decomposition to cause metallic deposition, it could hardly be referred to chemical action, but must result from direct stimulation of the sensory apparatus. Dr. Stone thought that a glimpse might thus be obtained of some correlation between the modus operandi of hearing and sight and that of taste. In the first case, a supplementary and automatic sensation, in the second the effect of a metallic solution, both entirely subjective, were excited without the presence of any sapid substance. The explanation may be that both classes of phenomena are due to molecular motion.
Do "Thorough-breds" revert?—The saying is a common one that domesticated animals tend continually to revert to the original or wild type, and do so revert if domesticating influences are withdrawn. At the Hartford meeting of the American Association for the Advancement of Science, W. H, Brewer, Professor of Agriculture in Yale Scientific School, called attention to this subject. He cites remarks made by an eminent scientist at a previous meeting as follows: "The hog has been greatly changed by domestication, and yet when left to himself he soon returns to the original type. During the late war some of the most improved breeds were turned loose and left to shift for themselves. Three years after I found them possessing all the physical characters of the wild-boar of Europe. He also stated that a similar fact had been observed with Durham cattle.
This statement, and all similar ones. Prof. Brewer sharply challenges. He refers to the confidence which owners and breeders of "thorough-breds" have in the permanence of acquired qualities; and says he has failed to find a single instance of reversion, nor has he found any one who knows of its having taken place. He suggests that the dogma (reversion) is used as an argument to sustain a certain scientific hypothesis. In order to ascertain the facts, Prof. Brewer has issued a circular containing the following inquiries, and promises to give the results obtained at some future meeting of the association:
"1. Have you personally ever known any ease where thorough-bred short-horn cattle, because of climate, poor feed, neglect, or any other cause, have become in character any thing else than short-horns—in other words, where from any cause thorough-bred short-horns have degenerated into animals of any other breed or type?
"2. Do you personally know of thoroughbred animals of any other breeds so changing or reverting?
"3. Have you ever heard of such a thing taking place, in the experience of other breeders, so well authenticated that you believe it to be a fact? "
The professor concludes his circular with the following remarks: "That grade animals often 'revert,' that curious freaks and 'sports' often attend violent crossing (and also that breeds deteriorate under bad management or bad conditions), are well enough known, but these facts do not affect the specific questions asked where the blood is supposed to be kept strictly pure."
Laborers' Homes.—Dr. Stephen Smith, in an address to the New York Public Health and Dwelling Reform Associations, points out various methods of improving the homes of the laboring classes in this city. He holds that every family almost may own a house for itself, and instances the city of Philadelphia, where tenement-houses are unknown, and where the day-laborer may, and does, occupy a house which is, or is in process of becoming, his own property. In the city of New York, south of the Harlem River, it is impossible for the poor to build houses, unless there be such a reconstruction of the land as will diminish the cost of individual lots, and allow of a larger number of single houses to the acre. Dr. Smith favors the plan of single rows of dwellings fronting at both extremities upon streets. Blocks thus laid out would have no inclosed courts, the dwellings would be flushed with free currents of air on both sides, and a much larger number of people could be accommodated in the same area.
The system of building associations, such as exist in Philadelphia, is highly commended by Dr. Smith. The relation of the laborer to the building association is thus stated: "He borrows $1,000 in cash, agreeing to pay $1,200 and the interest; he stands charged with $1,200, paying $60 per annum: it would take twenty years to pay up $1,200. But at the end of the time, his share being worth $1,200, he stops paying, and the house is his own. In fact, however, he is a participant in the profits, the premium and the interest he pays going to reimburse himself, and it only takes in practice ten or twelve years to put him in absolute possession of his home." Dr. Smith's address is worthy the attention of all classes; it is published in full in the Sanitarian for July.
In London, too, there exist various associations whose object is to provide improved dwellings for the laboring classes. At the present time these associations own 7,558 improved dwellings, capable of containing a population of 36,078. The buildings have been erected at a cost of about $6,000,000, and the enterprise is an undoubted financial success. But regarded from the sanitary and moral point of view the results are still more satisfactory. That the moral well-being of the inhabitants is promoted by the enlarged provision made in the model lodging-houses for the decencies of life is self-evident. The sanitary advantages possessed by these dwellings will be seen from a comparison of their death-rate with the death-rate of England in general, of London, or of any district of London. "There is not one year," says the Sanitary Record, "in which the death-rate prevailing in the model lodging-houses is not much lower than in England, and in the country, city, and town districts with which it is brought into comparison. Take, for instance, the healthy year 1868; it shows a death-rate in the model lodging-houses of 15 per 1,000, the most favorable figure for any mixed population of male and female being 22—a difference of 7 per 1,000 in favor of the model dwellings." It is a very significant fact that whereas in 1874 the death-rate of children under ten in the general population of London was 48 per 1,000, in the lodging-houses it was only 24 per 1,000. And the saving of disease must be in the like proportion. But yet in these dwellings the population is very dense, at least four times as dense as in the most thickly-peopled districts of London. Thus in the most populous district of the metropolis (Westminster) the population is 235 persons to the acre, while in the dwellings provided by the Metropolitan Association, including the large court-yards and gardens, the average is 1,140 to the acre: in one instance is
Rate of Growths of Corals.—It is stated by Prof. Joseph Le Conte, in the American Journal of Science, for July, that the well-known branching or tree-coral (Madrepora cervicornis) increases in the length of its branches by growth about 31⁄2 inches in a year. He came to this conclusion in the following manner:
At the Tortugas he found the prongs of this coral very near the surface, and all with their extremities at nearly the same level. All the prongs were dead for about the last three inches of their length, the lower limit of death appearing to be a perfectly horizontal plane. He ascertained that hundreds of acres were thus clipped, having the appearance of a clipped hedge, and he traced this result directly to a change of level of the ocean during each year. This change is about ten inches at Key West, owing to prevalent winds, the highest level being in September, the lowest in January. It is obvious that the branches of coral shoot upward with rise of water, and when near its greatest fall the new growth is destroyed. Lower down the corals are sufficiently beneath the surface to remain uninjured by the surface changes. The amount of dead coral indicates the growth, which is three inches for the growing period, or about 31⁄2 inches for the entire year for the madrepore-stems in this region.
Methods of Physical Culture.—At a meeting of the alumni of Amherst College, Dr. Nathan Allen made some remarks upon physical culture, showing that by right it must form an essential part of a college curriculum. He instituted a comparison between boating and ball-playing on the one hand and gymnastics on the other, and said that while the former are calculated to awaken public interest on the subject of physical culture, and to improve the physical condition of great numbers, yet as a means of health they are not the best adapted for the scholar. They call into exercise chiefly certain muscles of the chest, the spine and the limbs, and when long continued produce an abnormal development of these particular muscles at the expense of other muscles. But health rather depends upon an harmonious development of the whole body. Then, too, the exercises of boating and ball-playing become at times so violent and protracted as to cause congestion in the vital organs, resulting in serious diseases and endangering life. Furthermore, these exercises can be carried on only by a few individuals, in pleasant weather and at particular seasons—circumstances which render them unsuitable to the student.
With gymnastics it is very different. These can be carried on daily and systematically by all, with little loss of time or risk of injury to person or to good morals. They can be so varied as to call into exercise every muscle of the body, and, if need be, strengthen the weak parts and repress those in excess. While they are calculated to improve the general health, by producing a well-balanced organization, they aim to bring all the physical forces of the system into the most favorable condition for study and mental improvement. They tend to bring about the greatest possible harmony of action in every part, especially between the physical and mental, so that the machinery of body and mind shall work to the best advantage.
Distribution of Ferns in the South Pacific Islands.—M. Eugène Fournier, from a study of the 259 species of ferns native to New Caledonia, whereof 86 are special to that region, and the rest common to it and other groups of islands in the Pacific and Indian Oceans, has been led to the conclusion that at one time New Caledonia and New Holland, as well as New Zealand, were united by means of Norfolk Island and other submerged islands. This hypothesis, he says, will explain the simultaneous presence, in countries with different climates at the present day, of species belonging to homogeneous groups, which the currents would not have been able to transport in preference to others, and which, living in interior mountainous regions, are less exposed than littoral species to be drawn off by extraneous agents. As to the Mauritian Islands, it is very difficult to explain, by the fact of transport, the singular affinities connecting their flora with that of the oceanic isles. To suppose some lauds to have disappeared between Madagascar and Australia is a bold hypothesis which will, perhaps, impose itself one day on science—above all, after the results attained by geologists, and recently expressed according to the special studies of Alphonse Milne-Edwards.
The Prairie Gopher.—Among the burrowing species belonging to the squirrel family, the prairie gopher (Spermophilus Richardsoni) holds prominent rank. Though one of the most abundant animals in our country, infesting hundreds of thousands of square miles of territory, almost to the exclusion of other mammalian forms, the prairie gopher has but lately received the honor of an adequate description. This service has been rendered by Dr. Elliott Coues in the pages of the American Naturalist. The habitat of the prairie gopher appears to extend from the Red River of the North to the Rocky Mountains, and from latitude 38° to 55°. So numerous are they in Dakota and Montana that, according to Dr. Coues, should certain portions of these Territories ever be settled, the little gophers will contend with the husbandman for the land more persistently and successfully than the Indians can hope to. The animal seems to be a modification of the chipmunk; in the language of Dr. Coues, "If we take a chipmunk and crop its ears down close, cut off about a third of its tail, give it a blunter muzzle, and make a little alteration in its fore feet so that it could dig better," we have a pretty good prairie gopher. The holes they dig are small, but many of them, like the burrows of the badgers, foxes, and prairie wolves, will admit a horse's hoof. In some regions so numerous are these holes that it is impossible to gallop a hundred yards except at the risk of life or limb.
It is not easy to determine what particular kind of ground the gophers most affect. "Passing over a sterile, cactus-ridden, alkali-laden waste," says Dr. Coues, "there would be so many that I would say, 'This suits them best;' in camp that very night, in some low grassy spot near water, there they would be, plentiful as ever." If the animals have any preference, it is a choice of the lighter and more easily-worked soils; and they seem to haunt especially the slight knolls of the prairie a few feet above the general level. One gopher to a hole is the universal rule, nor has the author ever seen any signs of a burrow being occupied by a pair.
The female brings forth in June, but the young are never seen outside of the burrow till July, when they are about two-thirds grown. The number of young produced at a birth is supposed to be about eight.
Dr. Coues is of the opinion that the gopher is torpid during most of the winter. The animal hoards up food, it is true, but not in sufficient quantity to suffice for so active a creature during an entire winter. The author has often watched them, where the grass was taller than usual, gathering their store. They rise straight up on their haunches, seize the grass-top, and bite it off; then settling down with a peculiar jerk, they sit with arched back, and stow away the provender in their pouches, with the aid of their fore-paws. Their cheek-pouches, both together, would hardly hold a heaping teaspoonful. Though properly a vegetarian, the gopher derives no small share of his summer food from carcasses of buffalo.
Recovery from Lightning-Stroke.—In his valuable work on "The Maintenance of Health," Dr. Fothergill has the following on resuscitation after lightning-stroke: "Persons struck by lightning are not always dead when they appear to be so. There are few recoveries from this state, because no means are tried to restore the sufferer. In the tropics there are many instances of persons, struck down by lightning, recovering after a heavy thunder-shower; and it would appear that cold affusion to the body has a decided action in such cases. The injured cannot be harmed by the free use of cold water, and if only an occasional recovery took place it would be well worth the pains bestowed. The persons so injured should have cold water poured or even dashed freely over them."
The Air-Bladder of Fishes.—While engaged in measuring a degree of the meridian in 1806, the eminent physicist and astronomer Biot accidentally made the discovery that fishes living at great depths have the air-bladder filled with almost pure oxygen. Another French scientist, Dr. Moreau, has recently confirmed and extended this observation of Biot's. According to Moreau, the air-bladder secretes pure oxygen, and the presence of other gases is due to other causes besides the secretion of the organ. To prove this point, he examined fishes which had for a considerable time lived in very shallow water, and found, from several analyses, that the average amount of oxygen in the air of their swimming-bladders was about sixteen per cent. He then plunged the fishes in water to the depth of about twenty-five feet, and found that the quantity of gas in the air-bladder was increased. The oxygen was now from forty-five to fifty-two per cent.
New Fossil Ungulates from Mexico.—In a communication to the Philadelphia Academy of Natural Sciences, Prof. Cope describes some new fossil Ungulata found by himself while employed in the Wheeler Topographical and Geological Survey of New Mexico. One of these fossil ungulates, Pliauchenia Humphreysiana (a new genus and species), is regarded as representing a genus of Camelidæ intermediary between Procamelus occidentalis and Auchenia. P. Humphreysiana was of about the same size as the former of these two animals, or somewhat larger than any of the existing llamas. Another new species of this same genus is Pliauchenia vulcanorum, represented in Prof. Cope's collection by the left maxillary bone, which proves it to have been a camel of about the size of the existing dromedary, and considerably larger than the preceding species. The typical specimen was found near Pojuaque, a village of the Pueblo Indians. Various bones of camels of the size of P. vulcanorum were also found, some of which doubtless belong to the same species. Of Hippotherium calamarium, a new species of three-toed horse, the oral and palatine parts of the skull, with the superior dental series of both sides, were found near San Ildefonso. Dr. Cope points out the specific differences between this animal and Leidy's H. occidentale, H. speciosum, and H. gratum. Aphelops jemezanus, a new species of fossil rhinoceros, is represented by a right mandibular ramus, found near the town of Santa Clara, on the west side of the Rio Grande.
Parental Instinct in Fishes.—The Trinidad perch does not stand all alone among the finny tribes in caring for the safety of its young. A correspondent, after reading the article "A Motherly Fish," on page 126 of the present volume, writes us as follows: "I think it is known to our fishermen that the catfish watches over its young. For the fact that it does I can vouch. A friend whose place of business was on the quiet wharf of Havre de Grace, Maryland, had an opportunity, during more than a week and several times each day, of observing the parental care of this fish. There were always two fishes with the brood. When approached, one of these would dart off, while the other, naturally supposed to be the mother, could be seen to flap her tail against the bottom till a cloud of mud was raised, concealing herself and her little ones. When the observer remained perfectly still for some time, the water becoming clear again, the mother could be seen hovering over a dark mass of moving small-fry a foot or more in diameter, while a little way off the other fish would be in attendance."
Mouthless Fishes. Prof. Leidy lately exhibited at the Philadelphia Academy of Sciences an apparently mouthless fish, found in the Ouachita River, Arkansas. The fish is the buffalo sucker (Catastomus bubalus) an inhabitant of the Mississippi and its tributaries. The specimen is fifteen inches long. The maxillaries, premaxillaries, and mandible, are absent, and the integument is tightly extended between the end of the snout, the suborbitals, and the articular ends of the quadrates. In the centre of this expansion of the skin there is a small oval aperture one-fourth of an inch fore and aft, and one-eighth of an inch in transverse diameter. The hole is sufficient to admit a current of water for the purposes of respiration; but it is difficult to understand how the fish had procured its food. The cyprinoids generally are remarkable for their small, toothless mouth, but it is nevertheless important in its prehensile capacity. The condition of the specimen is of course a deformity, but appears to be the result of a want of development of the jaws, and not of accidental violence. Such fishes are often caught in the Ouachita, and occasionally even they have been reported without a vestige of an oral orifice. If the latter condition really occurs, the fish can only supply itself with food and with water for respiration through the branchial fissures, by the alternating outward and inward movements of the opercula.
Hatching Frogs under Colored Glass.—In an experiment made by M. Thury, the eggs of Rana temporaria, a species of frog, were placed under identical favorable conditions, with the exception that some of the eggs received light through colorless glass, and others through green glass. The former developed rapidly, and by the end of May had a length of over one and a half inch, and well-developed hind-legs in most of them; the others were slowly developed, blackish in color, hardly had a length of three-quarters of an inch by the end of May, and were without a trace of hind-legs. By the 10th of June the former had their fore-legs, and some were changed to frogs; the others, still black, had no trace of legs, and breathed almost exclusively by means of their gills. By the 15th of July the one lot had become frogs; the others still had no legs, and by the 2d of August they were all dead, without a trace of legs having appeared. Some of the young of this lot, transferred to the vessel in which were contained the developed frogs, finished their metamorphosis.
Equine Idiocy.—A plant known in California as "rattle-weed" is said to produce in animals which eat of it symptoms much resembling those of amentia and frenzy. A correspondent of a San Francisco newspaper, writing from Monterey County, describes as follows the effect produced by this plant on a herd of fifty horses on a ranche in the southern part of that county: "They became," he says, "crazy, forsook the farm, and wandered off one by one over the plain, paying no attention to their mates or any thing else. They were too muddled in their brains to seek for water, and most of them died of thirst. Although they were wild, and had never been handled, any person could walk up to them on the plain and hit them with his hand, when they would jump, perhaps, straight up in the air, perhaps some other way, and act as though they were trying to leap a fence at every step. They seemed to retain their sight, yet would not turn aside for any thing. The poor demented beasts would walk over a precipice without the slightest fear or hesitation."