Popular Science Monthly/Volume 13/October 1878/Popular Miscellany

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Popular Science Monthly Volume 13 October 1878  (1878) 
Popular Miscellany
 

POPULAR MISCELLANY.

Systematic Promotion of Research.—Prof. R. H. Thurston, Vice-President of the American Association, chose as the subject of his address to Section A, "The Science of the Advancement of Science." Having asked, "Why is the advancement of science to-day so apparently difficult and irregular and toilsome?" he attributed this state of things to the lack of systematic encouragement of scientific studies. The right men, he said, in substance, have never been sought out, and trained for this work. Men of science themselves have chosen rather to pursue their own favorite lines of research instead of investigating in the directions which would yield the best results. The endowment of research has not been urged with sufficient persistence. The materials and the apparatus placed in the hands of men of science for the prosecution of their labors have been too incomplete to permit the most effective application of their efforts. For these and other reasons we are not today, as we have not been in the past, prepared to do all that we should in the advancement of science and of the arts. By what practical measures, then, is scientific research to be promoted? The "science of the advancement of science" dictates that we shall seek:

1. To determine what are the most promising and most important directions of exploration in the great universe of the knowable.

2. That we shall endeavor to find young men fitted to become successful observers, discoverers, and philosophers; aid them to gain positions in which their talents may have full scope, and assist to make useful the results of their labor.

3. That we make it a part of our work to obtain for these investigators the means of research and the material aid which are necessitated by the rapid and ever-accelerating advances of knowledge for which we are indebted to them; to secure the endowment of new schools of science, the more complete organization of older schools, and liberal provision of apparatus and material for every investigator.

4. That we seek to improve our methods of instruction in science, to introduce into our educational systems a better scientific curriculum and far more extended courses, both of pure and of applied science, and to make the position of a teacher of science, viewed from the world's standpoint, a far more desirable one than it has yet become.

5. To make the organization and the operation of our academies of science, and of our societies for the advancement of science, far more thoroughly effective.

6. To endeavor to exhibit to both classes the fact that there exists between the man of science and the man of business a community of interests; the fact that he who accumulates wealth is largely indebted for his success to him who is unselfishly revealing to him the laws by which wealth is increased and business prosperity secured.

 

Proposed Silk-School Farm.—Certain capitalists in Philadelphia have signified their approval of plans of a silk-school, farm, and village, proposed by Mr. Samuel Chamberlain, and a company is to be formed for the purpose of putting the project into execution at an early day. In a communication to the Polytechnic Review, Mr. Chamberlain writes that the plans provide for legal interest on the investment, independently of the silk produced. They provide for a return of the capital by means of improved real estate, and for a profit beyond legal interest by retaining intermediate sections of the land, which, it is expected, will later be sold at a great advance, in consequence of the improvements. They provide growers of trees, silk-worm eggs, and silk, in addition to those to be produced by the school, namely, the renters of forty cottages, each surrounded by an acre of mulberry trees. They provide cottage culturers, and in a few years teachers of cottage culture, who will show by precept and example how silk may be raised in the midst of family duties. The danger of strikes is obviated by the fact that the renter of a cottage may in the end be an owner, and thus become directly interested in the uninterrupted progress of the work. In the school young persons will be trained to those habits of care, patience, and watchful attention, which are necessary for the successful raising and reeling of silk. The work is light and easy, and, when skill is acquired early, is highly profitable. It is peculiarly suitable for the deaf and dumb, whose misfortune cuts them off from so many occupations. When one such school shall have shown the way, like establishments will arise in many places; and in this way it is hoped to help in turning back into the country the tide of population now flowing into our cities. The failure to introduce silk-culture in 1840 was chiefly due to want of perseverance. The three years of actual trial were not enough to carry it on to success. But a school, farm, and village, whose continuance will be maintained sixteen to twenty years, will secure a permanent source of knowledge, example, and instruction, from which the culture will extend year by year.

 

Water for Domestic Uses.—The question of pure water-supply has been taken up for discussion by the London Society of Arts, and circulars have been sent out to civil engineers, sanitary officers, and other persons whose callings would appear to make them familiar with the conditions of the problem, inviting from them suggestions and plans for insuring to the whole population of England a sufficiency of pure water for domestic uses. A "Congress," too, has met in London, at which a number of papers, prepared by some of the most competent engineers and sanitarians, were read. In one of these papers, written by Mr. Samuel C. Homersham, the qualities of water fit for domestic uses are stated as follows: 1. Such water should be wholesome, free from animalcules or other organisms, animal or vegetable, either living or dead, and at no time or season of the year, or in periods of epidemics, liable to propagate disease or cause the death of those who drink it. 2. It should be soft and pleasant to use with soap both for washing the person and clothes, for baths and other detergent purposes, and of a quality such as would not dissolve lead, or form a deposit when boiled. 3. It should be clear and bright, agreeable to the eye, and refreshing to the taste. 4. It should be well aërated, of a nearly uniform normal temperature, and not like river or surface water, unduly warm in summer and unduly cold in winter. All that is needed, in the opinion of Mr. Homersham, and most of the other authors of papers, to insure abundance of such pure water, is that public opinion be educated to insist upon it. Works adequate to provide a regular supply of wholesome water, whether for towns or for small groups of dwellings in the country, might be constructed at moderate expense.

 

How Teleological Ideas are acquired.— In the course of his able address on "Education a Succession of Experiences," Prof. Grote, Vice-President of the Natural History Section of the American Association, remarks as follows upon the futility of teleological arguments: "From the imperfection and limitation of our senses comes not only a succession of experiences which are incomplete, but a general concept with regard to external matters, which must be of necessity misleading. We are here but a short time, and see little of the outcome of passing events, and can know nothing of the outcome of the world itself. Thus it has come to pass that what we have not fully observed we have assigned to an unknown cause. We have fitted Nature into our own measure, directly led thereto by the imperfection of our knowledge, and we have arrived at the concept that design exists in the world about us as it is displayed in our own handiwork and the work of animals, which, with ourselves, exhibit design in their operations. But in reality what we see in the details of the structure of animals and plants is not design, but adaptation. Suppose we leave a coat in a closet, and while it is there it is visited by a female clothes-moth, which deposits thereon numerous eggs. The little worms hatched from the eggs would at once commence to make free with the nap, and eat holes in the coat with a good appetite. If they ever thought about the matter, would they not conclude that the coat was hung there for their special benefit? They would do so merely because the coat was there. The fact that they adapted it to their own use would be construed by them into a belief that it was designed for their benefit. They would inevitably regard the owner of the coat, could they arrive at this conception, as their benefactor and the preserver of the whole race of maggots. They would know nothing of the thousands of clothes-worm eggs that perish because they never get anything to eat. The fact that life is sacrificed by the wholesale in Nature tells against the argument of design. And Nature is as careless of the species as of the individual. In the crust of the earth are contained the remains of millions of types of form of which Nature has not been careful, but has crushed them out, because they could not adapt themselves to the changing conditions which surrounded them."

 

Is the Evolution Theory atheistic?— Prof. Simon Newcomb's address, on his retiring from the annual presidency of the American Association, is a singularly lucid exposition of the state of the case as between the teleological and the mechanical explanations of the operations of Nature. The drift of his argument is best seen in the summary with which the address concludes, and which is in substance as follows: First, when men study the operations of the world around them, they find some of these plainly determined by law, while others appear to be purely arbitrary. This latter class of operations men attribute to the direct action of supernatural beings, gods; and they further ascribe to these gods aims, designs, to be attained through these interventions in the course of Nature. Further, men believe themselves able to discern these designs, and thus to explain these arbitrary operations. But, as knowledge advances, one after another of these operations is found to be really determined by law. Final causes having thus, one by one, disappeared from every thicket which has been fully explored, the question arises whether they now have or ever had any existence at all. On the one hand it may be claimed that it is unphilosophical to believe in them when they have been sought in vain in every corner into which light can penetrate. On the other hand, we have the difficulty of accounting for those very laws by which we find the course of Nature to be determined. Take the law of hereditary descent: how did such a law, or rather, how did such a process, first commence? If this is not as legitimate a subject for inquiry as the question how came the hand, the eye, or the first germ, into existence, it is only because it seems more difficult to investigate. When the doctrine of the universality of natural law is carried so far as to include the genesis of living beings and the adaptations to external circumstances which we see in their organs and their structure, it is often pronounced to be atheistic. Whether this judgment is or is not correct, Prof. Newcomb would not undertake to decide, but said that it is very easy to propound the test question by which its correctness is to be determined: "Is the general doctrine of causes acting in apparently blind obedience to invariable law in itself atheistic?" If it is, then the whole progress of our knowledge of Nature has been in this direction, for it has consisted in reducing the operations of Nature to such blind obedience. If the doctrine is not atheistic, then there is nothing atheistic in any phase of the theory of evolution, for this consists solely in accounting for certain processes by natural laws.

 

A New Calculating-Machine.—Mention is made, in the presidential address of Mr. Spottiswoode to the British Association, of a calculating-machine, devised by Prof. James Thomson, which for simplicity of construction compares favorably even with Edison's phonograph. The description given of this ingenious instrument is extremely meagre and insufficient, and does not give any notion of its modus operandi. "By means of the mere friction of a disk, a cylinder, and a ball," says Mr. Spottiswoode, "this machine is capable of effecting a variety of complicated calculations which occur in the highest application of mathematics to physical problems. By its aid it seems that an unskilled laborer may, in a given time, perform the work of ten skilled arithmeticians." It is applicable to the calculation of all sorts of periodic phenomena—as those of the tides, and of magnetic and meteorological variations. It will solve differential equations of the second, and perhaps even of higher orders. And through the same invention the problem of finding the free motions of any number of mutually-attracting particles, unrestricted by any of the approximate suppositions required in the treatment of the lunar and planetary theories, is reduced to the simple process of turning a crank.

 

Grass and Straw as Domestic Fuel.—The Mennonites, who, for a few years past, have been immigrating to our Western and Northwestern States and Territories from the Russian Empire, have introduced into their new homes the "grass-burner stove," by means of which their houses are warmed in winter, and all their cooking done throughout the year. The grass-burner is destined to be generally adopted by settlers in regions destitute of coal or timber, since by its use straw and dried prairie-grass are made to serve as perfectly satisfactory fuel. A description of this peculiar stove, with illustrations, is given by Prof. J. D. Butler, in the Gardeners Monthly, from which we copy the following notes on its construction and performance: The material is unimportant; some use brick, others stone, while still others prefer a mixture of sand and clay. The size is considerable, not unfrequently five feet in length, six in height, and two and one-half in width. The stove is erected as centrally as may be in a dwelling, so as to heat all the rooms as far as possible. The structure may be said to have six stories, viz., first, the ash-box; second, fire-box; third, cooking-oven; fourth, smoke-passage; fifth, hot-air chamber; sixth, smoke-passage to chimney or to a drum in an upper room. The fuel box is about four feet long, and in width and height a foot and one-half. The grass or straw is thrust in with a fork. The author says that, in the house of Bishop Peters, the grass or straw is pitched into the fire-box of the stove for about twenty minutes twice or at most three times in twenty-four hours; that amount of firing-up suffices amply for cooking and heating in the climate of Nebraska. It now remains for American ingenuity to improve on this Russian contrivance—to make it simpler, smaller, cheaper, of better materials, of more elegant design, and of more economical combustion.

 

How Mountains are made.—In a paper by Prof. Joseph Le Conte, read before the National Academy of Sciences in April, and since published in the American Journal of Science, the formation of mountains is explained by the action of horizontal pressure resulting from interior contraction of the earth. The author considers all the principal types of mountain-structure, and appears to account for them very satisfactorily by this theory of horizontal pressure. It would be impossible, within the limits of a Miscellany article, to give an intelligible outline of the entire argument, and we must content ourselves with a synopsis of the author's remarks on the formation of mountains of a single anticlinal fold—the simplest conceivable mountain-structure. Here

PSM V13 D782 Ideal section of an anticlinal fold.png
Fig. 1.—Ideal Section of Simple Anticlinal Fold (unsysmmetrical).

the deeper strata are thickened and swelled upward by the horizontal pressure, while the upper strata are raised into a vault with little or no thickening, or may even be thinned and broken by tension. The vault is nearly always unsymmetrical, the yielding being greater on one side than on the other. In such cases a great fissure and slip is apt to occur on the steeper side, as shown in Fig. 2. Perhaps the best illustration of a

PSM V13 D782 Fissured and folded anticlinal fold.png
Fig. 2.—The same, with the strata Assured and faulted.

range of mountains of this simple type is the Uintah Mountains. A cross-section of this range shows a prodigious fault of 20,000 feet on the northern or steeper side of the original fold. If the crust of the uprising region be extremely rigid, the vault, instead of being forty or fifty miles across, as in the Uintah Mountains, may be one hundred or several hundred miles across; we have then a great plateau. And since an arch of such span, whether filled or not beneath with fused or semi-fused matter, cannot sustain itself, such elevated plateaus are peculiarly liable to fissure by breaking down of the arch, and to slips by gravitative adjustment of the broken parts. The result is conspicuous escarpments or conspicuous mountain ridges in the general direction of the axis of the plateau. Such, according to the author, is the origin of the north and south escarpments of the plateau-region of the Colorado, described by Powell, and of the north and south monoclinal ridges in the Basin-region, described by Gilbert and Howell. Again, a monoclinal fold may be modified by metamorphism. This, says the author, is especially apt to be the case if the strata be very thick and the fold narrow and high; that is, if the compression in a given space, and therefore the heat of compression, be very great. If, now, such a sharp fold, metamorphosed in its deeper strata along the line of greatest compression, be subjected to profound erosion, it forms a common type of mountain, viz., one consisting of a highly-metamorphic axis, flanked on either side by tilted strata corresponding to each other.

 

The Differences between Atlantic and Pacific Forests.—The differences between the Atlantic and Pacific forests of the United States are very striking in many respects. Prof. Asa Gray, in a recent lecture, presents a long list of Atlantic forest-trees that are either not at all or but feebly represented on the Pacific slope. For instance, the Pacific forest has no magnolias, no tulip-tree, no papaw, no linden or basswood, and is very poor in maples; no locust-trees, nor any leguminous tree; no cherry-tree large enough for a timber-tree; no gum-trees, nor sorrel-tree, nor kalmia; no persimmon; not a holly; only one ash that may be called a timber-tree; no catalpa, or sassafras; not a single elm nor hackberry; not a mulberry, nor planer-tree, nor maclura; not a hickory nor a beech, nor a true chestnut nor a hornbeam; barely one birch-tree, and that only far north, where the differences are less striking. As to coniferous trees, however, the only missing type is our bald cypress, the so-called cypress of our Southern swamps. "But as to our ordinary trees," writes the author, "if you ask what takes the place in Oregon and California of all these missing kinds which are familiar on our side of the continent, I must answer, nothing or nearly nothing. There is the madrofia (arbutus) instead of our kalmia (both really trees in some places); and there is the California laurel instead of our Southern red bay-tree. Nor in any of the genera common to the two does the Pacific forest equal the Atlantic in species. It has not half as many maples, nor ashes, nor poplars, nor walnuts, nor birches, and those it has are of smaller size and inferior quality; it has not one-half as many oaks; and these and the ashes are of so inferior economical value that (as we are told) a passable wagon wheel cannot be made of California wood, nor a really good one in Oregon." He then states that, whereas the Atlantic forests contain sixty-six genera and one hundred and fifty-five species, the Pacific has only thirty-one genera and seventy-eight species.

 

Artificial Cold in the Treatment of Yellow Fever.—Dr. Bushrod W. James proposes, in the Philadelphia Ledger, a method of treating yellow-fever patients by artificial cold. He would have in every quarantine-station a ward or room capable of holding several patients, and so arranged that ventilation can be effected solely through ventilators and by means of small anterooms with spring-doors. There must be no entrance or exit to the ward save through the anteroom. The anteroom should be kept at the same low temperature as, or even lower than that in the ward, so that the temperature in the latter may not be raised by the opening and closing of doors by the attendants, nor any of the disease-producing germs escape before they are thoroughly subjected to the low temperature and destroyed. The ward and anteroom must be kept at a temperature not higher than 25° Fahr., the patients being made comfortable by a sufficient amount of bed clothing; and everything that goes from the room, such as clothing, excretions, all emanations, etc., must be exposed a sufficient length of time to the cold. This will kill the poisonous germs, or reproducing cause, and prevent, as far as the cases under treatment are concerned, any risk of the disease spreading. If patients cannot bear so much cold during treatment, an adjoining warmer room can be made, with no mode of access or ventilation except through the cold room, and everything going out of the warmer room must be allowed to remain a sufficient length of time to get rid of the contagion. If no attendant occupies the anteroom, the degree of cold can be kept near zero, in order the more quickly to destroy all the disease-producing agencies.

 

A Drought-Proof Fodder-Plant.—In a paper on the progress of agriculture in Natal, South Africa, Dr. P. M. Sutherland, surveyor-general of that colony, speaks of the advantages possessed by the Caucasian prickly comfrey (Symphytum asperrimum) as a fodder-plant, in regions characterized by annually-recurring seasons of drought. His remarks will doubtless be of interest to farmers settled in some of our States and Territories where like meteorological conditions exist. The plant named is allied to the borage, is a native of the mountainous regions of Circassia, and has long been used as forage both in that country and in Russia. Its original home is at a height of 4,000 feet above the sea, but it thrives well in a great diversity of climates, and bears hot and dry seasons with impunity, on account of the depth to which its strong root penetrates into the ground. There are two varieties of the plant, one with a hollow and the other with a solid stem. The latter is an excellent food for stock of all kinds; especially does it increase the quantity and improve the quality of cows' milk. It grows with marvelous rapidity and luxuriance. Land which yields eight tons of grass per acre gives from sixty to a hundred and fifty tons of comfrey. The plant is four or five feet high when near flowering, and the leaves attain a length of three feet. The flowers abound in honey. The solid stem is like a succulent root, and the plant is easily propagated by cuttings from this stem, containing a couple of eyes each. When once well rooted it will go on producing from fifteen to twenty years. The fodder may be cut six or even eight times a year; and if the leaves are stacked green, or partially dried, with a little salt between the layers, they keep well through the winter.

The Coat of the Rocky Mount Sheep.—Western huntsmen who have chased the Rocky Mountain sheep, or big-horn (Ovis montana), generally believe that the animal wears only a coating of hair, never wool; but, in a communication to the American Naturalist, Dr. F. M. Endlich shows that this is an error, and that the big-horn varies in the nature of its covering according to the seasons, being clothed with hair in summer, and with wool in winter. On July 17, 1877, Dr. Endlich, while engaged in work connected with the survey of the Territories, found himself among the Wind River Mountains, at an elevation of 12,000 feet above sea-level, and amid large fields of snow. While contemplating the scenery around, he heard the sound of tramping feet, and, looking up, saw four mountain-sheep approaching, though at first he scarcely recognized the species. They were of a totally different color from any he had seen before, and seemed to have a very rough skin. Eight days later Dr. Endlich ascended a high peak in the same range, and, as he reached the timber-line, he saw a band of over a hundred big-horns. Some of these he shot and killed. The "hair" was shorter than usual. It was apparently growing rapidly, and pushing before it a layer of very fine wool, about half an inch in thickness. In other words, the sheep were shedding their wool, which is exceedingly fine, and of a light-gray color. Some portions of the body were already clear of it. This explained the peculiar color and appearance of the sheep seen a week previously.

 

New Method of annealing Glass.—A new method of annealing glass is proposed by Messrs. Albert and Weyer, of Paris. It consists in burying the articles to be annealed in powdered stone, plaster, lime, etc., or in grease, oil, melted nitrates of potash and soda, in short, in any liquid or solid capable of receiving the required heat, and remaining in a condition suitable for the process. By imbedding the articles in powder, they can be annealed at a very high temperature—a thing impossible unless some means are provided for supporting the objects and maintaining their shape when reduced to the softened state necessary to secure perfect annealing. By the new process the articles are filled with the powdered stone or other substance, and are then placed in crucibles and completely surrounded with the pulverized substance employed. They are then subjected to a heat gradually increasing to 200° Cent., or even 1,000° C. from four to six hours, and are then slowly cooled. When there is little danger of spoiling the shape of the articles, they can be annealed by the use of liquids and at less cost. In this case two boilers are employed, so placed that the liquid can be run from the upper into the lower. If nitrate of soda is employed, the temperature will be over 260° C. before the salt is melted, and the articles are then immersed in the cold state, and the temperature raised to 800° C. Then they are allowed to cool slowly, and when the temperature has fallen to nearly 260° C.—the solidification point—the nitrate is run off into the lower boiler, and a small fire is maintained beneath the upper boiler to prevent the too rapid cooling of the glass.

 

Influence of Chemical Research on Character.— Prof. Maxwell Simpson, President of Section B of the British Association, in his address makes some very judicious remarks on the influence of chemistry upon the intellectual habits and moral character of its cultivators. He first notes how the study of chemistry, or rather original chemical work, promotes accuracy, thoroughness, and circumspection. An organic analysis requires six weighings; if any one of these is inaccurate, the results are worthless. Unless the analyst is sure of every step in his research, his results are doubtful, and therefore of no value. Again, the original worker must be ever on his guard against error, and laboratory-work teaches us to use our senses aright, sharpens our powers of observation, and prevents us from reasoning rashly from appearances. Then, as regards the effect of original work on the character, in developing the virtues of courage, resolution, truthfulness, and patience: the chemist is often obliged to perform experiments which are attended with great danger, and no man can hope to fight long with the elements without carrying away many a scar. Sometimes fatal accidents occur. But the chemist must not be discouraged by fear of accident, neither must he be disheartened by the temporary failure of his experiments, nor at the slowness of his processes. "Bunsen was obliged to evaporate forty-four tons of the waters of the Dürcheim springs in order to obtain two hundred grains of his new metal, cæsium. It took Berthelot several months to form, by a series of synthetical operations, an appreciable quantity of alcohol from water and carbon, derived from carbonate of baryta. Many years ago, in the laboratory of Wurtz, a poor student was carrying from one room to another a glass globe which contained the product of a month's continuous labor, when the bottom of the globe fell out, and the contents were lost. Nothing daunted, he recommenced his month's work, and brought his research to a successful issue. Above all things, the chemist must be true. He must not allow his wishes to bias his judgment or prevent him from seeing his researches in their true light. He must not be satisfied that his results appear true, but he must believe them to be true; and, having faithfully performed his experiments, he must record them faithfully. He may often be obliged to chronicle his own failures and describe operations that tell against his own theories, but this hard test of his truthfulness he must not shrink from."

 

A New Form of Galvanic Cell.—When rods of zinc and copper are placed in mercury, and connected with an electrometer, no change is observed; and, whether the zinc and copper are in contact outside the mercury or not, the amalgamation of the zinc appears to proceed at the same rate. According to a communication to the London Royal Society, from Profs. Ayrton and Perry, of the Tokio Engineering College, the impurities and great conductivity of the zinc, with the great liquidity of the amalgam, and the close proximity of foreign particles to pure metal, cause the amalgamation to be produced by local action alone, so that the supply of available chemical energy for the production of a current from the zinc to the copper is exceedingly small: at low temperatures, when the amalgam loses its liquidity, such an arrangement would, the authors conjectured, become a simple voltaic cell. To test this they substituted, for zinc, magnesium, whose amalgam is nearly solid at ordinary temperatures. Strips of platinum and magnesium, metallically attached to the electrodes of the electrometer, were dropped into mercury which had been washed with distilled water and then well dried. There was a sudden large deflection, afterward fluctuating very much, but keeping always on the same side of zero. On successive reversals of the electrometer key, the deflections to the right and left of zero were found to be nearly equal to one another. To determine the electro-motive force of the arrangement, strips of platinum and magnesium, scraped very clean, were dipped into pure mercury. The maximum electromotric force obtained was 1.56 volts—equal to one and a half time the electromotrive force of a Daniell cell. The authors remark that, by mechanical or other means, or by using another metal than magnesium, it may be possible to give constancy to this arrangement; and as its internal resistance is extremely small, the cell may be of great practical use for the production of powerful currents. As an amalgam may be easily separated into its components by distillation, such a cell might be kept in action for an indefinite time.

 

An Interesting Geological Question.— Though the Triassic rocks of New Jersey and the Connecticut Valley are commonly regarded by geologists as intrusive igneous rocks, the direct proof of their intrusive nature is not readily accessible. Indeed, some geologists have supposed that, so far from being intrusive, they were formed contemporaneously with the shales and sandstones amid which they occur, as a bed of igneous rock at the bottom of a shallow sea in which the stratified rocks were being deposited. But Mr. I. C. Russell shows, in the American Journal of Science, that these trap-rocks were forced out in a fused state among the sedimentary strata after the consolidation of the latter, and hence that they are more recent than either the rocks above or below them. The evidence of this he finds in a ravine on the western slope of the First Newark Mountain, directly west of Westfield, New Jersey. Here the trap-rock which appears in the bed of a little brook presents its usual characteristics of a hard, bluish, crystalline rock, with a conchoidal fracture. In other places it swells up into bosses and rounded masses which are thrust up into the overlying rocks. The outside of these masses presents a scoriaceous or slag-like appearance; in the interior the cavities are filled with infiltrated minerals. For the first two or three feet above the trap the shales which rest directly on these igneous rocks have been intensely metamorphosed, and are scarcely to be distinguished from the trap itself. At a distance of six or eight feet above the trap the shales are still very much altered and filled with a great number of small spherical masses of a dark-green mineral, resembling epidote. Midway up the sides of the ravine, which is about thirty feet deep, the shales present somewhat of their usual reddish appearance, but are traversed by a great number of irregular cavities formed by the expansion of vapor while the rocks were in a semi-plastic condition. At a distance of twenty-five or thirty feet above the trap, the shales and sandstones are changed but slightly, if at all, from their normal condition. A bed of limestone from two to three feet in thickness, which is here interstratified with the shales and sandstones where it approaches the trap, is considerably altered and forms a mass of semi-crystallized carbonate of lime. All this furnishes indisputable evidence that the igneous rocks composing the First Newark Mountain were intruded in the molten state between the layers of the stratified rocks subsequent to the consolidation of the latter; and by analogy we are justified in extending this conclusion to all the trap ridges which traverse the Triassic regions of New Jersey.

 

Agricultural and Mineral Resources of Alaska.—The following notes on the mineral and agricultural wealth of Alaska we take from a communication published in the Chronicle of San Francisco. The Territory is as yet virtually unexplored, yet gold, silver, copper, graphite, lead, iron, sulphur, and coal, have already been found in sufficient quantity to pay for working the deposits. "Eight well-defined ledges of gold-bearing quartz have been prospected on Baronoff Island, close to the town of Sitka; their owners owe their discovery and partial development to the enterprise and energy of one Haley, who was formerly a soldier of the garrison that was stationed here. Haley began to utilize his gold discoveries about three years ago by quarrying out rock and crushing it in a common hand mortar. By this primitive process he obtained money enough to support his family and pay the cost of a visit to Portland and San Francisco in search of capital to develop his mines. Little is known of that section of Alaska which lies back of the coast between Cross Sound—where the Alexander Archipelago, with its 1,100 islands, ends—and Prince William's Sound. On Prince William's Sound are several Indian villages, and several tracts of prairie-land which may be easily cultivated. Beyond this large inlet lies Kodiac and Cook's Inlet. As a fishing and agricultural district this is undoubtedly the best section of the whole Territory of Alaska. The climate is milder, the winters less severe, and the rainfall less, than in the southern counties of Scotland. Both on Kodiac and the shores of Cook's Inlet are large tracts of prairie-land, which now afford excellent pasture for cattle and sheep, and which can be easily cultivated for all the hardy vegetables, barley, and oats. Timber is abundant and easily accessible from the water. A large deposit of coal has been prospected, the quality of which is declared by Prof. Newberry to be fully equal to any coals found on the Pacific coast, not excepting those of Vancouver Island and Bellingham Bay. The Indians who come-down to the head of the inlet report large deposits of native copper a short distance inland, and exhibit ornaments and utensils of the same. Lead of sufficient purity to be moulded into bullets is also found there. The waters literally swarm with fish; and it is safe to say that there is no district of country on the whole Pacific coast which offers so many advantages for the profitable establishment of fish-canning and fish-curing works. With a comparatively moderate investment of capital, exports of fish to the value of several millions of dollars annually may be sent from Cook's Inlet, which would pay a large profit to the owners of the works, and would support many thousand fishermen, laborers, and mechanics. Nothing but the power of monopoly has hindered Alaska's growth thus far."

A New Theory of the Flow of Sap.—In a new theory of the ascent of sap in trees, proposed by Joseph Böhm, the elasticity of the plant-cells plays an important part. When the superficial cells have lost through evaporation a portion of their water, they partly collapse under the action of the air-pressure; but, like elastic bladders, they tend to resume their original form. This they can do only by drawing in either air or water from without. But since moist membranes are but little permeable by air, the cells draw from the cells farther toward the centre a portion of their liquid contents; these in turn draw on the cells farther down, and so on down to the roots. The author illustrates his theory by an apparatus which represents a chain of cells. A funnel closed by a bladder represents the evaporating leaf; to it are connected below several glass tubes about two inches wide, closed at one end with a bladder, and joined together in series by means of thick caoutchouc tubes. As evaporation goes on, the membrane which closes the funnel-mouth is bent inward, and, when it has reached a certain tension, water is sucked into the funnel out of the cell next below, which covers its loss in the same way. Manometers connected with certain cells of the apparatus indicate the amount of suction at different heights.