Jump to content

Popular Science Monthly/Volume 20/February 1882/Popular Miscellany

From Wikisource

POPULAR MISCELLANY.

Value of Soil Analysis.—Professor E. W. Hilgard, in a paper in the "American Journal of Science," on "The Objects and Interpretation of Soil Analyses," accepts as correct the principle that, other things being equal, productiveness is, or should be, sensibly proportional to the amount of available plant-food within reach of the roots during the period of the plant's development, provided that such supply does not exceed the maximum of that which the plant can utilize, when the surplus simply remains inert. For finding the exact value of the soil from analysis, it is necessary, however, not so much to find the actual amounts of the constituents in the soil, as to find the amounts which are accessible to and assimilable by the plants. The problem is, then, to find a solvent which shall as nearly as possible represent the action of the plant itself. Analyses of European soils fail because virgin soils do not exist in Europe, and no generalizations can be drawn from the examination of any spot. In the United States we still have perfectly natural soils in nearly every part of our territory, with the original vegetation, which reveals so much to the farmer, still growing upon them. Professor Hilgard's method of analysis starts from the observation of the productive qualities of the soil as indicated by the native growth. He then tries to ascertain what are the peculiarities of the soil that favor this kind of growth, as distinguished from some other growth on some other soil. As a rule, a soil showing a high percentage of plant-food is fertile; but the converse is not always true; a soil having a low percentage is not necessarily poor. A loose soil, by enlarging the sphere of expansion of the roots may enable them to reach as large quantities of food, even when it is more widely scattered, as they can find in a more highly charged but more compact and less penetrable soil. Hence mechanical conditions should always be taken into account. The analyses so far instituted prove that, other things being equal, the thriftiness or present productiveness of a soil is measurably dependent on the presence of a certain minimum quantity of lime.

The evidence on this point is "overwhelming." The lime operates by effecting the more rapid transformation of vegetable matter into active humus, by retaining the humus against the oxidizing influence of hot climates; by rendering minute percentages of phosphoric acid and potash effective; by a tendency to secure the proper maintenance of the conditions of nitrification; and, physically, by promoting the flocculation of the soil. After that of lime, the proportion of phosphoric acid seems to be the most important factor in the productiveness of soils. A certain percentage of potash is required, but it is present in most soils; and Professor Hilgard infers, generally, that "potash manures are not among the first to be sought for after the soils have become 'tired' by exhaustive culture." Iron, in the shape of ferric hydrate finely diffused, appears to be an important ingredient, valuable on account of its physical, and partly also of its chemical qualities. It has a high absorptive power for gases, and soils in which it occurs resist drought better than others; and the universal preference given by farmers to red lands shows the results of experience in this respect. The efficiency of the hydrate depends essentially upon a state of fine division; and when merely incrusting the sand-grains, or aggregated into bog-ore grains, it exerts little or no influence, although the analysis may show a high percentage. On the other hand, ferruginous soils are the first liable to damage from imperfect drainage, overflows, etc.

The Eocene Strata of Alabama.—Mr. Angelo Heilprin has communicated to the Academy of Natural Sciences of Philadelphia an effort to arrange the Eocene deposits of Alabama, determine their depth, and fix their relative position in the geological system. For this purpose he has given comparative reviews of the examinations of various exposures, including the Claiborne Bluff and sections on Bashia Creek, Clarke County, and at points on the Tombigbee River. The Claiborne Bluff was formerly considered to be near the base of the Eocene system, but it appears to be underlaid by the strata which crop out at other points, indicating a thickness of at least 200 feet, if not more, of Eocene posits beneath it, and a total thickness for the whole system in this region of nearly 400 feet; indeed, Dr. Smith, the State geologist, states that there are good grounds for supposing that tertiary beds exist in the northern part of the State, whose position would be 150 to 180 feet below the Wood's Bluff marl-bed, which is near the base of the Tombigbee beds. The Claibornian bed would then be placed in a position near the top of the series, a position almost precisely similar to that occupied by the Calcaire Grossier (Parisian) of France, and more properly Upper than Middle Eocene. The Alabama Eocene deposits are arranged on this scheme by Mr. Heilprin as follows: 4. "White Limestone" (Jacksonian), but exhibited at Claiborne (upper part of bluff) and at St. Stephen's on the Tombigbee (lower half of bluff), not very abundant in fossils, 50 or more feet; 3. The fossiliferous arenaceous deposit (Claibornian), but shown at Claiborne—subaqueous at St. Stephen's—very rich in fossils, and of the age of the "Calcaire Grossier" of France, 17 feet; 2. Buhrstone (siliceous Claiborne of Hilgard), comprising siliceous clay-stones densely charged with fossils or their impressions, laminated clays, sands, and calcareous deposits, about 250 or more feet; 1. The Wood's Bluff and Bashia deposits (with Cane and Knight's Bluff branches) (Eo-lignite), consisting of alternating dark clays, greenish and buff sands, and numerous seams of lignite, partly very rich in fossils, and, as far as is yet positively known, the oldest tertiary deposits of the State, 50 or more feet. The author intends to discuss in a future paper the relations of these deposits to those of other parts of the United States, and to correlate them, if possible, with the typical Eocene deposits of Europe.

Australian Snakes.—A correspondent of "Land and Water" relates some interesting particulars concerning Australian snakes and their peculiarities. Among the largest is the carpet-snake, or boa, which grows to be ten or a dozen, even eighteen feet long, and as thick as a man's leg, is destructive to poultry, sluggish by day, nocturnal in its habits, and of harmless bite. Most of the black snakes are highly venomous, and one, with a scarlet belly, is very handsome and active. The color of snakes depends upon the season when they change their skins. During the hot season the reptile is far brighter in tint, and far more active and poisonous, than when the temperature is low. The color also varies much with the habitat. Thus, the death-adder is nearly red in a red soil country, black and gray in black soil, and brown on sand, and is exceedingly sluggish, trusting to the adaptation of his color to the ground he crawls upon for safety. Nothing is more remarkable about snakes than their extraordinary faculty of making themselves invisible. A large carpet-snake can hardly be seen, as he lies along a branch or coiled motionless in the fork of a tree whose bark exactly matches his skin in color. The green tree-snakes are invisible among foliage. "Take your eye for a moment from a snake among bushes or grass, and you will hardly ever see him again." Two yellow snakes lived in the correspondent's house, among the rafters or in the linings of the walls, where their presence was known by the casts of their skins which they left, for two years, without being seen or heard. Evidence of the existence of great numbers of unseen snakes is afforded by the multitude of tracks, which may be seen in the dust of a road following along a water-course. Snakes seldom advance to attack a man, but generally try to get away from him, and go toward him only when he is between them and their place of refuge. The Australian snakes, even the most venomous, can not fairly be called dangerous. The correspondent never knew personally of a case of a bite fatal to human life, though he has often seen the reptiles coil themselves round the legs of horses and bullocks, "with strong presumption in every case of a bite," but never knew of any injurious result. Many cats and dogs, however, learn to kill snakes, "but almost always end by missing their tip once, and fall victims to over-confidence in themselves"; and the blacks eat all sorts, whether venomous or not, provided they kill the former kind themselves.

Hawaiian Leprosy.—Dr. A. W. Saxe has lately made a report to the California State Medical Society on leprosy in the Hawaiian Islands, which is partly based on observations made during a visit to the leper settlement on the Island of Molokai in February, 1880. The Hawaiian leprosy does not differ essentially from the disease in Europe and Asia, but its history is known from its origin, and its development there may be traced with greater accuracy of detail than in other countries. It was introduced from China with the coolie-trade, and was first recognized in 1848. Its spread has been furthered by the peculiar habits of the people, particularly in eating, and their close association in their houses, and is contributed to by the exhaustion caused by the use of the intoxicant kava. To this may be added impure vaccination, which was practiced indiscriminately by all classes of people in 1852, and the prevalent licentiousness, which is hardly concealed. All observers agree that the disease is hereditary and that death alone ends it. It is established that it is a specific and well-marked disease—not a form of syphilis—that it exists in two varieties, the tubercular and anæsthetic, which may be distinct or associated, that it is not contagious, but is transplantable, and that men are more liable to it than women. The treatment has heretofore been merely palliative, the most useful drug in affording relief being the bark of the hoang-nan-tree. The most effective preventive of the spread of the disease is isolation. Few of the children born of leprous parents survive infancy and none survive adult age. Hence, is suggested the possibility of stamping it out if the lepers can be kept separated from the rest of the population. The population of the Pacific States are in no immediate danger from leprosy, but the increasing intercourse with China and the Sandwich Islands, combined with prostitution, offers a constant menace, and makes vigilance a duty.

The Real Discoverer of Spectrum Analysis.—Mr. Frank Cowan makes, in the "Pittsburg Telegraph," a strong presentment of the claims of the late Dr. David Alter, of Freeport, Armstrong County, Pennsylvania, who died last September, to be regarded as the real discoverer of spectroscopic analysis. Dr. Alter was born in 1807, and manifested at a very early age an interest in the study of electrical phenomena, and later in chemistry. He invented and perfected an electric telegraph in 1836, which, being more cumbrous than Morse's, and even than Wheatstone's, he never attempted to bring into use. He also invented an electrical engine, and published a paper on electricity as a motive power in 1837. His papers on spectrum analysis were published in the "American Journal of Science" in 1854 and 1855, five years before Kirchhoff announced his discoveries. The first paper, published in the number of the "Journal" for November, 1854, was "On Certain Physical Properties of Light, produced by the Combustion of Different Metals in the Electric Spark, refracted by a Prism." After describing the appearance of the light of the sky, of a petroleum-lamp, of a tallow candle, the flame of alcohol, and the light from heated wire or charcoal as seen through his home-made prism, he gives accounts of the "separate colored bands" which he observed in the spectra of the sparks caused by the break of the galvanic or magnetoelectric circuit, from points of silver, zinc, copper, lead, tin, iron, bismuth, antimony, brass, and combinations of metals. The second article appeared in May, 1855, and was "On Certain Physical Properties of the Light of the Electric Spark within Certain Gases, as seen through a Prism." This paper is explicit, and contains a paragraph suggesting the application of the author's discovery to the detection of the elements in the aurora borealis, shooting-stars, and luminous meteors. An abstract of the first paper was published in Liebig and Kopp's "Chemico-Jahresberichte" for 1854. The second article was reproduced entire in "L'Institut," of Paris, in 1856, and in the "Archives of the Physical and Natural Sciences" of Geneva, vol. xxix, p. 151. A full-page extract from it, containing its most suggestive statements, was also published in Kopp and Will's "Jahresberichte" for 1859. Kirchhoff announced his discovery in the year last mentioned.

Organic Remains in Meteorites.—Professor J. Lawrence Smith expresses a strong disbelief in the alleged discovery by Professor Hahn of organic remains in meteoric stones. He says that, although he has probably examined more microscopic plates of fragments of meteorites than any other person, he has never discovered anything like organic remains in any of them. Besides, he adds, "the well-known chemical composition of these bodies is averse to the exigence of any such remains as are spoken of by Professor Hahn. Were these remains present, we should discover carbonate of lime in their interior. The two or three that have any carbonate of lime were discovered and analyzed by myself, and in those cases the carbonate of lime was an accidental constituent of incrustation deposited on the surface after their fall. In the microscopic examination of the polished plates of meteorites the two predominating minerals, enstatite and bronzite, will, by their fissures and forms, sometimes remind one of vegetable and other organic forms, but the merest tyro of an observer will trace here nothing but a rare resemblance. And, furthermore, the very igneous nature of these minerals precludes the possibility of organic remains, even in terrestrial minerals of a similar kind. Professor Hawes, of the Smithsonian Institution, who is familiar with lithological microscopical researches in Germany, agrees with Professor Smith, describes Professor Hahn as an observer whose "imagination has run wild with him," and regards his observations as not entitled to credit.

Obituary.—American science has lost during the last month two of its most distinguished names. Lewis H. Morgan, the anthropologist, died at his home in Rochester, New York, December 17th, of a complication of disorders, from which he had suffered for several months, at the age of sixty-three years. We have recently (November, 1880) given a sketch of his life and his principal investigations and writings. His fame has been growing and the influence of his ideas extending for many years; and it has long been usual to see him quoted as an authority whose views were entitled to the highest respect, even when dissented from, in the anthropological discussions of all nations. Professor John William Draper, M. D., LL. D., died at Hastings-on-the-Hudson, January 4th. He was born near Liverpool, England, Hay 5, 1811, came to the United States in 1833, was graduated in medicine at the University of Pennsylvania in 1836, and began the connection as professor with the University of the City of New York in 1839, which he maintained till the end of his life. He assisted in founding the medical department of the university in 1841. He was closely identified with the progress of chemical science in the United States, particularly in connection with the investigation of the chemical action of light, and of the temperature of incandescence, and in the early history and development of photography. His most noteworthy works were his treatise "On the Forces which produce the Organization of Plants," which marked an epoch in this branch of investigation, and his "History of the Intellectual Development of Europe," which has been translated into nine languages. He also published books on "Human Physiology, Statical and Dynamical; or the Conditions and Course of the Life of Man," "Thoughts on the Future Civil Policy of America," the "History of the American Civil War," and a "History of the Conflict between Religion and Science," all of which have made their mark; and text-books in chemistry and natural history. A fuller account of Professor Draper's life and works is given in the "Popular Science Monthly" for January, 1874, and frequent references to his later labors may be found in subsequent volumes.

Influence of the Electric Light on Plant Life.—M. P. P. Déhérain has just published the results of the experiments he conducted during the Exposition of Electricity at Paris, on the influence of the electric light upon vegetation. A conservatory was built within the palace, in which plants were disposed in four groups, each receiving a different treatment. One group was deprived of the light of day and was exposed to the electric light all the time; another had the diffused daylight, weakened by having to pass through the glass roofs of the Exhibition Palace, by day, and the electric light at night; a third group had only the diluted daylight by day and was left in the dark at night; and the fourth group, kept during the day in a shaded garden-bed, and was taken into the conservatory and exposed to the electric light at night. Some plants, which were taken into the conservatory a few days before the electric apparatus was put in operation, suffered badly from the deficiency of light—much more than the experimenter had anticipated they would. The plants that were constantly exposed to the electric light became marked with spots, and began in the course of eight days to give evidence of having received serious injuries. That the spots were caused immemediately by the light and not by the disengagement of nitrous vapors, was shown by the fact that only the leaves and parts of leaves that were exposed directly to the light were touched. This satisfied M. Déhérain that the electric light contains rays that are detrimental to plant-life; and the facts indicate that these rays are the violet ones. A direct trial of the capacity of the electric light to decompose carbonic acid was made, with the result that less gas was evolved from plants continuously exposed within twelve feet of the light for several days than is given out in an hour in the sunlight. Plants that enjoyed the light of the conservatory by day and received the electric light at night, suffered less, but were not healthy. The electric light was inclosed in globes of transparent glass and a new set of experiments was instituted with new plants. The mischievous effects of the violet rays were no longer perceived, but the light was not capable of maintaining a healthy growth. The plants started well, but sent out long, thin shoots, which withered and died. Nothing but barley reached a condition near maturity. None of the plants would bloom; but some of them died at the top and took a new start from the root—to wither and die again. Continued experiments showed that these results were due to the lack of power in the electric light to promote the activity of evaporation required to bring the plants to maturity. The plants that were kept in the weakened, diffused light of the conservatory by day, and in the dark at night, fell into a gradual decay. Those that spent the day in the shade out-of-doors, and the night under the electric light, did better, but not much better, than they would have done if they had been left undisturbed out-of-doors. M. Déhérain concludes that the electric light has sufficient power to keep plants alive that would die in the dark, and that it exerts enough positive influence upon vegetation to account for the seemingly favorable results of M. Siemens's experiments, in which vigorous plants that had the light of day, and would have done well anyhow, were made to do better by being given also the electric light at night.

Word-Blindness.—M. Magnan, in a communication to the Société de Biologie, has related two cases of aphasia complicated with a special phenomenon, to which he has given the name of word-blindness. One case was that of a man who was seized with a right hemiplegia and aphasia after a fall. A month afterward, the patient recovered the power of speech, little by little: he understood spoken language; he wrote, of his own accord or from dictation, but was incapable of reading either print or manuscript, even when the latter had been written by himself; and he could not name letters written upon a board. The second patient presented similar symptoms. He recognized objects which were shown him, but could not name them; could write words thought or heard, but could not comprehend what was written. He had lost the notion of the value of gesticulations. A similar case is reported by M. Brunardel, in which a post-mortem examination revealed a disordered condition adjoining the pli courbe. The pathology of the affection is explained by supposing that the communications between the psychic visual center, which is situated about the pli courbé, and the convolutions of Broca, are interrupted. In such a case, the patient can still see, speak, and hear, but can not acquire any new idea through his eyes. "Brain" suggests that since no disease of the eye exists, and the affection is owing to a purely psychic phenomenon, it might be better described as "cerebral word-blindness."

Death of Dr. J. B. Davis.—Dr. Joseph Barnard Davis, an eminent British authority on skulls, died in May last, at about eighty years of age. He made a voyage to the Arctic regions as surgeon to a whaling ship in 1820, while still a medical student, then settled down in the potteries of Staffordshire as an apothecary. An accidental conversation with a friend turned his attention to anthropological studies, on which he published several memoirs, more particularly relating to the craniological branch of the subject, the most important of which was perhaps the "Crania Britannica," containing delineations and descriptions of the skulls of the aboriginal and early inhabitants of the British Islands. He was an industrious hunter after specimens, and formed at his house a collection of crania and skeletons larger than the collections in all the public museums in the country put together, and which has been surpassed only in very recent years by any of the Continental collections. The catalogue of this collection, the "Thesaurus Craniorum," published in 186*7, contains descriptions and many figures of the specimens, with twenty-five thousand measurements and a large fund of information. The collection was so much increased afterward that a supplement to the catalogue was published in 1875. The two works contained descriptions of seventeen hundred specimens. The collection has been transferred to the College of Surgeons of England.

Congresses of German and Austrian Archæologists.—The Twelfth Congress of German Archæologists met at Regensburg, August 8th, the members having, previous to assembling, visited a local collection of prehistoric and Roman antiquities, illustrating the history of the settlement of the Danube for two thousand years, and listened to an address by Professor Fraas, on the geology and history of Regensburg from its beginning. The report of the general secretary, Professor Ranke, gave a summary of the general progress of archaeological science during the year, and referred especially to the exhibition at Berlin, and the publications connected with it, as having increased interest in the science; to Professor Fraas's review of the primitive history of the country in the Stuttgart catalogue; to the results of the Congress at Lisbon, and to the evidence that had been found, in the Iberian Peninsula and Hungary, of a distinct copper age forming a transition to the bronze age. The list of special publications was quite full, and included essays by Tischler, Voss, and Virchow, on sewing-needles, belt-clasps, treasures, and urns; of Liebe on a former submergence of Thuringia; of Mehlis on the discoveries at Kirchheim on the Eck, and the Hermundurs and Thuringians; of Rosenstein on the spread of flints through trade; of Fischer on the traffic in nephrite; of Ochlenschläger and Herzog on the cartography of the discoveries in Bavaria and Würtemberg, and of other writers on single objects of prehistoric research. The study of local names had been advanced by the labors of Buck in Swabia and Schulenberg in Brandenburg, and Voss has made special studies on formulas of incantation and the blessing of swords. Herr von Tröltsch exhibited a series of four elaborate maps of the archaeological discoveries in Schleswig-Holstein, in which the several classes of rocks and relics were very distinctly indicated by colors. Professor Schaafhausen reported, upon the progress of the general catalogue of the anthropological material of Germany, that special catalogues of the collections in the principal cities and universities are already completed or in hand, and those of societies and private persons will be taken up next. After spending three days in listening to a series of interesting papers, the members of the association went to Salzburg to meet with their fellow-workers of the Austro-Hungarian Association. The sessions here were more lively, and were marked with greater interest than those at Regensburg, for they were characterized by free discussions of every topic, while the proceedings at Regensburg were confined to the reading of the papers. Count Gundiken Wurmbrand, President of the Austro-Hungarian Association, delivered the opening address, referring chiefly to the Etruscan relics found in Austria, the evidences of Celtic culture on the Danube, and the significance of popular ethnography in prehistoric research. The first day's session was occupied with a very lively discussion of the "Celtic question," that is, the question whether the later Germans were ethnologically identical with the earlier Celts, or whether the two were distinct stems. Other interesting discussions were those concerning the period of the mammoth, and concerning the diluvial human relics found in Stramberg. The reports of the German society stated that it now included fifty-eight local unions or groups, and about twenty-three hundred members.

Development of the Mammalian Foot.—Professor E. D. Cope has suggested as a result of his studies of the feet of the mammalia, that the reduction in the number of toes in the ungulates "is due to the elongation of those which slightly exceeded the others in length, in consequence of the greater number of strains and impacts received by them in rapid progression, and the complementary loss of material available for the growth of the smaller ones. This is rendered probable from the fact that the types with reduced digits are dwellers on dry land in both orders, and those that have more numerous digits are inhabitants of swamps and mud." The cloven-footed animals were mud-dwellers, as a few of them still are, and larger than the whole-footed ungulates; and "the mechanical effect of walking in the mud is to spread the toes equally on opposite sides of the middle line. This would encourage the equal development of the digits on each side of the middle line, as in the cloven-footed types." On the other hand, in progression on hard ground, the longest toe (the third) will receive the greatest amount of shock from contact with the earth, and there is every reason to believe that shocks, if not excessive, encourage growth in the direction of the force applied. The hinge between the first and second series of tarsal bones in cloven feet is also supposed to be the result of strains endured in walking in mud. The variations in the degree of development of the trochleæ, or the prominences forming the tongues of the tongue-and-groove articulations, in different mammalia, also seem to be dependent on the amount and kind of strain to which the limbs are subjected.

The Archæological Congress at Tiflis.—A very interesting Archæological Congress was recently held at Tiflis, which was attended by about eight hundred persons, nearly all from Russia and the Caucasus. Professor Virchow was the most conspicuous foreign delegate. Collections of stone and bronze antiquities and Georgian ornaments were exhibited from Russia, Kuban, and Ossetia, where great numbers of bronze implements, carved hatchets with spiral, zigzag, and animal ornaments, and religious objects belong to some unknown worship, have been found in recent years. Count Ouvaroff made a communication on remains of the stone period human skeletons, with stone and bone implements, perforated teeth of animals, and as many as two hundred jade (nephrite) hatchets, the first jade implements observed in graves in Russia, which had been found on the bank of the Angara River, near Irkutsk. In the discussion concerning jade that followed the reading of this paper, M. Moushketoff described the great monolith of jade over the grave of Tamerlane at Samarcand, which is 7·8 feet long, 1·5 foot wide, 1·2 foot high, and weighs about eighteen hundred pounds, or more than twice as much as the largest pieces of nephrite that have been found in bowlders. Professor Samokoff gave an account of his finds in the graves near Pyatigorsk, in the Caucasus. He excavated about two hundred graves belonging to the stone, bronze, and iron periods, and found in the larger graves bronze and stone implements, bones of sheep, and several split human bones that did not belong to skeletons. His conclusion that the Caucasians of the bronze age were anthropophagists was not concurred in by the majority of the Congress. Professor Virchow gave a lecture on the chief problems of the ethnology and archæology of the Caucasus. On the current opinion that the Caucasus was the highway for populations coming from Asia to Europe, he expressed some doubts whether the Caucasian passes could have been crossed by whole tribes at a time when communications were so difficult, and the ice-covering descended lower than now. It would be most important, therefore, to ascertain whether the first inhabitants of the Caucasus came from the north or from the south. He considered that the civilization which the antiquities found in Ossetia represent was far more recent than that discovered by Dr. Schliemann at Troy.

Acoustics in Architecture.—Mr. A. F. Oakey, the architect of the Cincinnati Music Hall, gives some valuable suggestions on "Acoustics in Architecture" in "Van Nostrand's Engineering Magazine." The most essential requisite to a good music hall or hall for public speaking is, that it should bo, as to its dimensions, in harmonic proportions. By this is meant that the length, breadth, and height of the room should bear some simple, easily determinable proportions to each other; generally one corresponding with the commensurate ratio borne by the intervals between the tones of the musical scale, which is expressible by the numbers from one to six. Harmonic proportions may be represented by the combinations 6: 2: 8, 6: 5: 3, 2: 5: 3, 2: 2: 4, 2: 3:4, or others as simple. Angles, being a disturbing element, may be obviated by adopting curved surfaces, but these must not be circular, for we should then have a whispering gallery, nor elliptical, for then the sounds would be concentrated in the foci; but they should be in the shape of a parabola having its focus very near the contour. The seats should rise toward the back of the room, to correspond with the tendency of the sound to rise with the, ascending currents of air, and to prevent its being caught in the clothing of the audience. A system of ventilation should be adopted that will rather carry the sound toward the audience than in the other direction. When the amount of space for each person exceeds one hundred and ninety-five cubic feet, the walls and ceilings should be finished with resonant material; where the amount of space is less than this, the finish should present a repellent, hard, and unsympathetic surface like plaster, or like stone if the space is less than one hundred and fifty feet. The obstructions presented by the supporting-posts and the acute angular recesses of galleries may be avoided by constructing the gallery upon a system of curved iron supports beginning on the floor line against the wall and rising with a gradual parabolic curve outward, the spaces between which should be filled in with wood or plaster surface. In the light of these principles, Mr. Oakey can "see no excuse for building an apartment so that its acoustic properties shall not be as much a matter of course as keeping out the weather." Mr. Oakey also considers the sonority of party-walls, for which he suggests furring, with lathe and plaster and the removal of the bearings of floor-joists from the walls, as cheap and efficient remedies.

Heat and Health.—A sufficiency of heat is one of the most essential requisites to health; and in the administration of heat we have one of the most powerful curative agents. The sun furnishes a constant supply of beneficial warmth, of which we make much less use than we might and ought. Indeed, we too often shun that which we ought to seek, as when we deliberately and at considerable cost darken the rooms into which we ought to welcome the sunshine, or carefully exclude its life-giving rays with umbrellas and parasols. The idea of a sun cure, which was proposed by one of our physicians several years ago, was one of genuine merit, and has been strongly commended, after several years of observation in the East, by the late Mr. David Urquhart, M. P., and secretary to the British embassy at Constantinople, who has related many incidents illustrating its efficacy. Among them was that of a person who had been advised, at the baths of Gastein, to try air baths in the neighboring forests. He received considerable benefit from lying undressed in the shadiest part of the forest, but finally concluded to expose himself in the full sunshine. Although he had always supposed that the rays of the sun gave him headache and derangement of the stomach, he found that when entirely exposed he was not unpleasantly affected in any degree, but felt agreeable sensations of genial warmth. If, however, he covered any part of his body, the disagreeable feelings returned, and the covered part became intolerably hot. Occasionally a pricking and itching sensation and redness of the skin suggested the suspension of the baths for a day or two. Dr. Scanzoni, of Wurzburg, explains the freedom under these baths from the pains in the head and stomach which commonly follow exposure to the sun by the fact that the action is diffused equally all over the body, and the circulation is determined in a corresponding manner, instead of being drawn in excess to the head. Dr. Gosse, of Geneva, wrote in 1826 in high praise of the curative properties of heat, which he regarded as working by restoring the action of the skin. The hot-air bath has been used for twenty years in the Newcastle Infirmary with satisfactory results, and has been introduced into several lunatic asylums with most excellent effects in soothing and curing mania and the attendant diseases. Dr. Lockhart Robertson, of the Sussex County Lunatic Asylum, not only recommends it in those cases, but says that he has had several examples of its curative power in the early stages of consumption, and believes that, if used at a sufficiently high temperature, the results would astonish us all. Mr. Urquhart observes that a high temperature is more endurable when the heat is radiant than when it is brought in hot air-currents.

Association of German Naturalists and Physicians.—The fifty-fourth meeting of the Association of German Naturalists and Physicians was held at Salzburg, September 18th to 24th. The first secretary of the association, Dr. Günther, of Salzburg, in his address of welcome, mentioned the fact that Salzburg was the last place of retirement of Paracelsus; and that great physician and naturalist was the subject of a special address by Dr. Kirschensteiner, of Munich, at the closing session. The meeting was divided into twenty-three sections, eleven of which were medical, and seven pertained to natural science. Besides Professor Pettenkofer's paper on the sanitary relations of the soil, which we publish, Professor Weisman read a paper maintaining that in general the duration of life of an individual represents the minimum of time necessary to insure the existence of the species, and is governed by adaptation and heredity. Professor Meyners, of Vienna, in an address on the laws which govern human thoughts and actions, expressed the opinion that the phenomena of bodies do not disclose to us their essence, and that there is only a phenomenon of freedom of will. At the third general meeting, Professor Oppolzer, of Vienna, disputed the sufficiency of the theories of the moon, Mercury, and Encke's comet, based upon Newton's law of gravitation in its present form, and postulated the hypothesis of a cosmic matter surrounding the sun as necessary to complement them and make them sufficient.

Animals and the Telegraph.—M. Nielsen, director of the Norwegian telegraph lines, has just published a curious note upon the impressions that are produced upon animals by the vibrations of telegraphic wires. The posts in the neighborhood of the Norwegian pine-woods, even those which have been freshly impregnated with sulphate of copper, are frequently found to have been perforated by woodpeckers, which, it seems, mistake the humming of the wires for the buzzing of insects. The holes arc generally made near the insulators, and a post shown at the Paris Electrical Exhibition had a hole clear through it large enough to insert the whole arm. Bears imagine the humming to be that of bees, and, not finding any sign of a colony above, paw at the heaps of stones at the base of the poles; and, when they can find nothing, vent their spite in a vigorous blow on the ground, to kill the bees that persist in staying hid. The scattering of the heaps of stones around the posts, which is not rare, could not be explained, till some one perceived the marks of the bears' claws where these desperate blows had been given. Wolves are believed to have been frightened away by the lines. While a vote was pending on a grant to a telegraphic line, a member of the Storthing remarked that, while his constituents had no direct interest in the line, they would support the grant, because the wires would drive away the wolves. It is said that, however hungry a wolf may be, he will never go into a spot that is inclosed by ropes stretched on posts. It is a remarkable fact that since the first telegraphic line was established, twenty years ago, wolves have never appeared in its neighborhood.