Popular Science Monthly/Volume 16/April 1880/Popular Miscellany

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Popular Science Monthly Volume 16 April 1880  (1880) 
Popular Miscellany


The Old River-Beds of Middle California.—Old river-beds are found in nearly all countries which have been affected by drift agencies. They are also found in California, but, while in other parts of that State they present general features similar to those of the Eastern States, those of the auriferous slate belt of middle California are entirely different in character and in their situation as respects the present river-beds, and are in some respects unique. In most other countries the present river-beds occupy the same position as the old; the rivers of middle California have been displaced by lava-flows from their former position, and compelled to cut entirely new channels. Instead of cutting these channels at a higher level than the older ones, as has been usually observed, the displaced rivers in California have cut them two or three thousand feet deep in the solid slate, leaving the old detritus-filled channels far up on the dividing ridges. In other parts of the United States the drainage system has remained substantially unchanged since Tertiary times, but in this California region the new drainage system is entirely independent of the old, having the same general direction, but sometimes cutting across it. The detritus in the old river-beds of California is composed of large pebbles and bowlders, instead of the silts generally found, and is capped by lava or other volcanic material. In these observations Professor Joseph Le Conte and Professor Whitney substantially agree. Professor Le Conte has made a further study of the phenomena, and has given his conclusions in a paper in the last number of the "American Journal of Science." The old stream-beds, as they arc exposed in the processes of hydraulic mining, are shallow, lowest in the middle and rising to the sides, with such forms ground upon the surface of the bed-rock at their bottom as are always produced by swift currents carrying coarse materials, and are in marked contrast with the deep, sharply Y-shaped cañons which characterize the present rivers in the same region. The filling up of the beds consists of a lower course, sometimes a few feet, sometimes many feet in thickness, of a conglomerate of pebbles and bowlders of; considerable size, cemented with sand and a blue clay. Above this are alternate layers of pebbles, gravel, sand, and clay, with fragments or trunks of trees of the Pliocene age, and bones of the mammalia of the Pliocene and Quaternary ages, and perhaps human relics. Above the detritus is a capping of volcanic matter, a tufaceous conglomerate, with or without basalt over it. Professor Le Conte accounts for the singular phenomena by a theory, the principal features of which are that the old drainage system began to be formed after the birth of the Sierra Nevada, at the close of the Cretaceous period, and continued to exist through the Tertiary; the Sierra rose during the Glacial period, accumulated great masses of snow and ice and glaciers that were to play a part in filling the beds, and made the courses of the rivers much steeper than they had been before. The eruptions which threw out the volcanic products were preceded by a period of underground heat which melted the accumulated ice-masses. The waters and ice rushing in violent torrents brought down the coarse gravels and masses of rock, and dropped them as they became too great a load for the streams to carry. Afterward came the eruptions, first of ashes, then of lava, which flooded the mountain-slopes and completely obliterated the drainage system. Coincidently there were a considerable elevation of the Sierra range and an increase of the mountain-slope. The glaciers and rivers now began to cut a new system of channels independent of the old ones. They preferred the old divides, for the lava was thinnest or wanting there. As a necessary consequence of the increased elevation, the new channels were cut down to a level below that of the old ones.


Age of the Green Mountains.—Professor James D. Dana gives, in the "American Journal of Science" for March, his reasons for having in the new edition of his "Geology" referred the epoch of the formation of the Green Mountains—in the system of which he includes the whole region between the Connecticut and the Hudson—to the close of the Lower Silurian period. They are, when summarized: 1. That the western half of the region is proved to consist of rocks of the Lower Silurian age, and of one {{hwe|orological system; 2. The schistose rocks of the eastern half, in Vermont, are to a large extent similar to those of the western; 3. The rocks of the central mountain section in Vermont are, in its northern part, identical schists with those on the east and west sides of it; 4. The western border of the region in the Hudson River Valley has its folded or upturned Hudson River (Lower Silurian) slates overlaid unconformably by the Niagara and Lower Helderberg (Upper Silurian) beds; 5. The eastern border of the region in the Connecticut Valley at Bernardston, in Massachusetts, Vernon, in Vermont, and the adjoining part of New Hampshire, has Lower Helderberg beds overlying, unconformably, folded or upturned roofing-slates (similar to those on the western side), the Lower Silurian age of which is not improbable; and at Littleton, in New Hampshire, and on Lake Memphremagog, in northern Vermont, occur unconformable Upper Helderberg (Lower Devonian) beds with fossils; 6. A mountain-individual of folded rocks—which is defined as comprising all the elevations or results of upturning or flexure that were produced over a continuous region in one mountain-making process—is necessarily one of great magnitude. Professor Dana does not consider his theory as established, for a further study of the stratigraphy of the eastern part of the region is required for that, but he believes that the facts, which he reviews in detail, are strongly in its favor.


Gas and the Electric Light.—The question of the feasibility* of substituting the electric light for gas is yet far from settlement. The competition will be finally decided by the consideration of the relative expense, regard being also given to the quality of the light afforded. Some experiments which have recently been made for increasing the illuminating power of gas have been attended with satisfactory results. The most effectual devices are those by which a more perfect combustion is secured. By concentrating a number of burners so arranged as to play upon each other, and by improved arrangements for regulating and directing the draught of air upon them, the amount of light has been tripled, and it has been made clearer and more fixed. Burners constructed with this object in view have been tried in London, and found to give a considerable increase of light at a less increase of expense. Other devices, produced by French inventors, promise well. The inventors of electric lights seek either to produce single lights to supplement the defective illumination given by ordinary lights, or to divide the light, so as to make it take the place of gas entirely. The apparatus devised by Messrs. Regnier and Werdemann and Mr. Edison, for the latter purpose, give an agreeable light; but that is only a part of the problem. The difficulty of securing an economical production and supply of electricity remains, and that equally whether we seek to distribute it so that each consumer shall use only what he needs, or to store it in reservoirs of force. Experiments which have been made upon the amount of light produced per horse-power of motive force give greatly varying results. The light of M. Mersanne, with the Lontin machine, is rated at 80 carcels; the Jablochkoff light, with the Gramme machine, at 38 carcels; and Mr. Edison's machine, with 10 of his carbon lamps, at 16 carcels. A comparative trial of the strength of the Jablochkoff and Mersanne lights and gas was made in the latter part of December at one of the railway-stations in Paris. Six of the Jablochkoff lights, ten compound intensive gas-burners, and four Mersanne lights, were used. The brilliancy of the gas-light was to the Mersanne light as 1 to 5·67, and to the Jablochkoff light as 1 to 1·927. On direct comparison, the brilliancy of the Jablochkoff was to the Mersanne as 1 to 3. Roughly, 6 Mersanne lights were equivalent to 1 8 Jablochkoffs and 34 gas-jets.


Composition and Uses of Celluloid.—Celluloid, which has come into extensive use in the arts, is a species of solidified collodion, produced by dissolving gun-cotton in camphor with the aid of heat and pressure. From a description of its composition and mode of manufacture by Dr. W. H. Wahl, we gather the following: The process of preparing gun-cotton is well known; by it the properties of the vegetable fiber are so changed that it becomes soluble in alcohol and ether, as in making collodion, camphor, and other substances. In the process invented by the brothers Hyatt, gun-cotton is ground in water to a fine pulp; the pulp is then subjected to powerful pressure in a perforated vessel, to extract the bulk of the moisture, but still leaving it slightly moist for the next operation, which consists in thoroughly incorporating finely comminuted gum-camphor with the moist gun-cotton pulp. The proportions employed are said to be one part by weight of the camphor to two parts by weight of the pulp. Any pigments, coloring matter, or other materials that may be adapted to the requirements of the articles into which the product is to be manufactured, may be incorporated at this stage. The mass is next subjected to a powerful pressure, to expel from it the remaining moisture, and incidentally to effect, also, the more immediate contact of the camphor with the pulp. The dried and compressed mass is next placed in a mold open at the top, into which fits a solid plunger, when a heavy pressure applied to the plunger is brought to bear upon the mixture. While thus under pressure, the mixture is heated to a temperature of about 300°, at which temperature the camphor fuses, and, its volatilization being impossible, the melted camphor dissolves, or "converts," the gun-cotton pulp. The process of transformation is rapidly effected when the right temperature is reached, and the product is celluloid. After the mass is taken from the press it hardens and becomes tough and elastic. A noteworthy circumstance is, that a large portion of the camphor appears to be permanently held in the mixture, so that its property of volatilization, when exposed to the air, is arrested. Celluloid is so extensively used as a substitute for ivory that it is said to have seriously affected the business of ivory importers and workers. It has all the strength and elasticity of this substance, and docs not warp or discolor with age. It is used in place of tortoise-shell, malachite, amber, pink coral, and other costly and elegant materials, which it is made to imitate very closely. Its latest use is in combination with linen, cotton, or paper, for shirt bosoms, cuffs, and collars.


Experimental Glaciers.—Mr. J. T. Bottomley describes in "Nature" a successful experiment which has been arranged by himself and Mr. D. Macfarlane for constructing a model glacier with shoemaker's wax. A little wooden ravine was prepared, with steep declivities and gentle slopes, and a point where the space was narrowed by projections inward. At the upper end of the ravine a flat place was fixed, on which shoemaker's wax was piled, as snow collects at the upper end of the natural ravine. A supply of shoemaker's wax was put on the top at the beginning of each winter's session, whence a flow of semi-solid material went on steadily during the session, hardly perceptible from day to day, but progressing from week to week and from month to month. Several of the glacial phenomena were beautifully imitated with the wax; among them the more rapid flow of the middle with the less rapid flow at the edges. Little crevasses were sometimes formed, though not often, owing to the great effect of temperature on the plasticity of the material. Sir William Thomson, in order to test the qualities of shoemaker's wax as a viscous material, a year ago prepared a large cake of it, at the bottom of which he put some corks, and on the top some bullets. The corks at the end of the year had floated up through the wax, and were coming out at the top, while the bullets had sunk down and come through the bottom; and, while this was going on, the wax was all the time in such a condition as to be excessively brittle to any force suddenly applied.


Source of the Niger.—Information has reached Marseilles of a successful journey to the source of the Niger, which has been made by two men in the employment of the commercial house of M. Verminck, of Sierra Leone. The expedition, it appears, originated with M. Verminck himself, who sent forth two of his clerks, MM. Zweifel and Moustier, with an equipment of surveying instruments, maps, and goods, for the express purpose of reaching the spot on the northern side of the Kong Mountains, some two hundred miles from Sierra Leone, where both Major Laing, in 1822, and Winwood Reade, in 1869, were informed by the natives lay the sources of the "Joliba." The two envoys ascended the river Kokelle to the foot of the mountains, and seem to have met with none of that opposition, from the chief of the important town of Falaba, which defeated the attempts both of Laing and Reade to reach the sources. The crossing of the mountains appears, however, to have been a difficult undertaking, not accomplished without much determination, aided by good luck. The main source was found on the frontier of Kirsi and Koranka; in short, near the place indicated on Major Laing's map.


Animal Heat of Fish.—Surgeon J. H. Kidder, of the United States Navy, made some observations during last summer in connection with the United States Fish Commission at Provincetown, Massachusetts, to test the belief which is still held by many, even scientific observers, that fish are cold blooded—that is, that they take on the temperature of the water which surrounds them, with no power to resist it, and that they develop little or no animal heat themselves. Observations made in the usual way, by inserting the thermometer into the rectum of the fish, agreed with the generally received opinion, the fish showing in that part but little higher temperature than that of the surrounding water. It was judged, however, that neither the rectum, which is closely exposed to the water, nor the arterial blood, which has passed through the gills where it is exposed and cooled, could have the same value as representing the body-temperature in fishes that corresponding parts possess in mammals and birds, but that the degree of heat actually developed in the life-processes should be sought in the venous circulation and the branchial artery. The fish were accordingly opened as soon as possible after they were taken out of the water, and the bulb of the thermometer was inserted into the cavity of the heart, or the branchial artery. Most of the fishes showed a perceptibly higher temperature than that of the water, rising, in the case of the dogfish, to 12°. A young dogfish, taken from its mother's oviduct, was 20° warmer than the water. The number of observations was not large enough to warrant a final statement of the degree of animal heat presented by the several fishes, but they are held to prove that fish develop sufficient heat to warm again, to the extent of from 3° to 12°, blood that has been cooled in each circuit to the temperature of the surrounding water. An apparent exception to the general result was offered in the case of bluefish, which were cooler than the water; but that was supposed to be because they had come up from a greater depth and a colder stratum of water than that on the surface.


Sun-Spots and Rainfall.—Mr. E. D. Archibald writes in "Nature" that, instead of changes in the condition of the sun necessarily affecting every part of the earth in the same way, we have many meteorological analogies which favor the notion that totally opposite effects may arise in different parts of the earth from the action of the same primary causes. Thus, it is generally assumed that the same tropical heat which gives the primary impulse to the desiccating northeast trade-wind of subtropical latitudes, furnishes the energy which exhibits itself in the almost constant precipitation under the equator. Any variation in the degree of this heat should consequently affect places in the region of the trades and in the equatorial calm-belt, in a diametrically opposite manner. The great rainfalls of last autumn in England and India were ascribed by some to the sun's emergence from a period of years marked by the rarity of its spots, and shining with increased radiations on the southern oceans; but Mr. Archibald shows that the rainfall of England, between latitudes 50° and 55° north, reached a decided maximum in 1877, a year of extreme spot-minimum, and was very high all through the recent period of unusually marked spot-minimum. A table of the annual mean range of barometric pressure at Calcutta from 1840 to 1878, of which Mr. Archibald gives a summary in his communication, indicates that years of few sun-spots were characterized by higher temperatures, greater wind-velocity, and greater range of barometric pressure than those of many spots.


New Bleaching Preparation.—A method of applying the ordinary bleaching agents (hypochlorites) in a new way has been invented by Count Dienheim de Brochocki, of Paris. Instead of immersing the goods to be bleached in an ordinary "chloride-of-lime" vat, and subsequently scouring, the inventor treats bleaching-powder with an acid, and simultaneously passes air through the mixture, so that chlorine and hydrochlorous acid vapors are mechanically carried off; the resulting gases are passed through an alkaline solution in such proportions as to saturate part or the whole of the alkali, or to supersaturate it at will. The resulting liquid is said to be sufficiently stable to be kept without change for two or three months; it can readily be prepared of a density of 30° Beaumé, and acts as a bleacher without requiring any acidulation, and for many purposes is said to be superior to the ordinary bleaching-vat. The new product, to which the inventor has given the facifulname of chlorozone, is used to a considerable extent in Paris, and works for its manufacture on a large scale have been erected at Warrington.


Effects of Excessive Tea-drinking.—W. J. Morton, M. D., of New York, gives in the "Journal of Nervous and Mental Disease" an account of investigations which he has made on the toxic effects of tea. They were carried on in the cases of five tea-tasters suffering from disease who came under his care, and in observations of his own symptoms during a week in which he subjected himself to special treatment with tea for purposes of experiment. From the whole series of observations he draws the conclusions that—1. With tea, as with any potent drug, there is a proper and an improper dose; 2. In moderation, tea is a mental and bodily stimulant of a most agreeable nature, followed by no harmful reaction. It produces contentment of mind, allays hunger and bodily weariness, and increases the disposition and the capacity for work; 3. Taken immoderately, it leads to a very serious group of symptoms, such as headache, vertigo, heat and flushings of body, ringing in the ears, mental dullness and confusion, tremulousness, "nervousness," sleeplessness, apprehension of evil, exhaustion of mind and body, with disinclination to mental and physical exertion, increased and irregular action of the heart, increased respiration. Each of the above symptoms is produced by tea taken in immoderate quantities, irrespective of dyspepsia, or hypochondria, or hyperæmia; 4. Immoderate tea-drinking, continued for a considerable time, with great certainty produces dyspepsia; 5. The immediate mental symptoms produced by tea are not to be attributed to dyspepsia; 6. Tea retards the waste or retrograde metamorphosis of tissue, and thereby reduces the demand for food. It also diminishes the amount of urine secreted; T. Many of the symptoms of immoderate tea-drinking are such as may occur without suspicion of tea being their cause, and we find many people taking tea to relieve the discomforts which its abuse is producing.


Antiquity of the Tobacco-Pipe.—The discovery of large numbers of pipes, apparently of considerable age, in Great Britain and parts of the Continent of Europe, has given rise to new and extravagant conjectures as to the antiquity of the tobacco-pipe in Europe. From an article in "The American Antiquarian," by Mr. Edwin A. Barber, we learn that these ancient pipes are very small, and are found in great numbers in the British Isles, where they are known as fairy pipes, Celtic or elfin pipes, Dane's pipes, Mab pipes, old man's pipes, and Carl's pipes. A number of them have been found so near to Roman remains as to induce the belief that they are Roman relics; but other undoubtedly modern remains have been found in a similar connection. The pipes resemble modern ones in shape, and often bear manufacturers' marks, which make it practicable to estimate their age. The oldest of them are supposed to have been made during the reign of Queen Elizabeth. Probably the oldest illustration of a tobacco-pipe in Great Britain is in a carving on a chimney in the keep of Cawdor Castle, where among the devices are a mermaid playing the harp, a monkey blowing a horn, a cat playing a fiddle, and a fox smoking a tobacco-pipe. This stone bears the date of 1610. Mr. Jewitt suggests, in his "Ceramic Art in Great Britain," that herbs and leaves were smoked medicinally long before the period at which tobacco is believed to have been introduced, and that pipes may have been in use for this purpose before "the weed" was known. British pipes may be classified according to age, with some degree of certainty; by form, as they were developed from exceedingly small pipes with flat heels to larger barrel-shaped pipes, and then to pipes with long handles and pointed spurs. The makers' marks were put on the heels of the oldest specimens, on the bowls of more recent ones, and on the stems of still later ones.


Stammering and its Causes.—M. Chervin, founder and director of the Institution for Stammerers, at Paris, has recently made researches into the prevalence of stammering in France, as shown by the reports of the recruiting officers for the army during the last twenty years, and into the climatic and other influences that are favorable to the development of the infirmity. He has represented the results of his inquiries by a map which exhibits the relative number of stammerers in each of the departments at a glance. The map shows that the country may be divided into two distinct parts, by a lino running from Bordeaux to Geneva, on the south of which the number of stammerers is vastly greater than it is on the north of it. The proportion of stammerers to the whole number of young men who have reached the age when they are liable to conscription appears to be about five to one thousand. The districts along the Mediterranean coast seem to be the most liable to the affliction; and it has been found that stammering is also extraordinarily frequent in Piedmont, which has a similar climate and population. M. Chervin attributes the origin of the habit in this region partly to the extreme animation of the speech of the southern people, partly to the hot winds which are the cause of nervous disorders with which stammering may be connected. Stammering may be produced by a sudden fright suffered during childhood. Sometimes the habit comes on gradually, or is developed by association with stammerers. Men appear to suffer more from it than women, as all authors agree, so that out of a hundred stammerers hardly more than ten or twenty will be women. This may, however, only signify that men feel more inconvenience from the evil and notice it more. The reports of the recruiting officers show that the proportion of stammerers is three or four times less in the cities than in the country; a fact that is very suggestive by the side of another which M. Chervin has brought out, that stammerers arc most rare where there are the most schools. It is evident that as youth become more accustomed to using their language and learning to distinguish words, to spell and write them, they learn to have a clearer conception of them, to articulate more distinctly, and escape confusion. The great number of stammerers in savage countries has been observed by travelers. It is ascribed to the absence of a knowledge of their language, and to the frequent repetitions of the same syllables which appear in their words.


Investigating the Lightning-Rod.—Delegates were appointed in the summer of 1878, by a number of British societies, to consider the possibility of formulating the existing knowledge on the subject of the protection of property from damage by electricity, and the advisability of preparing and issuing a general code of rules for the erection of lightning-conductors. These delegates have held several meetings, and have already collected a large amount of information. Several of their number are also engaged in forming abstracts of the literature of the subject. In order that their report may be as trustworthy and exhaustive as possible, the delegates ask, through Mr. G. J. Symons, their secretary, for information to be communicated to them by correspondence, on the following points: "Full details of accidents by lightning, stating especially whether the building struck had a conductor or not. If there was a conductor, state its dimensions, construction, mode of attachment to building; whether its top was pointed, distance of its upper terminal from the place struck, nature and extent of the connection between the conductor and the earth, and whether the earth was dry or moist; whether the conductor was itself injured, and whether the conductor or the point struck was the most salient object in the vicinity. Information is also desired, either verbally or by sketches, as to the position of metal spouting and lead roofing relatively to the point struck, and to the conductor. Details of the thickest piece of metal melted by a flash of lightning are much needed. Unimpeachable evidence of the failure of conductors is much desired, as such failures would be extremely instructive."