Popular Science Monthly/Volume 32/March 1888/Popular Miscellany
POPULAR MISCELLANY.
The Panama Canal.—At the meeting of the Academy of Sciences held in Paris, January 9, 1888, M. Ferdinand de Lesseps made a communication in relation to the proposed changes in the Panama Canal, of which the following account is taken from the "Journal des Débats": "What is now being done—and this will enable the largest vessels to pass from one ocean to the other in 1890—is the ship-canal just as it was agreed upon by the International Congress, and just as it should be on the original line; only, instead of waiting until it shall be completely finished, in order to open it to navigation, we have simply decided to do again that which was considered best for the Suez Canal in 1865—that is, at a time when formidable opposition, both political and financial, particularly financial, threatened to ruin the enterprise just as it was about to be finished. We have merely decided to open the canal to navigation as soon as possible when we shall be able to have ships as large as those of the Transatlantic Company pass from one ocean to the other, and a sufficient number of them to bring the annual traffic up to seven and a half million tons, as was predicted by the International Congress. This traffic assures us an annual revenue of one hundred and twenty million francs; it will enable us to settle all our indebtedness, and to pay a first dividend on the shares, and will still leave us something over. It is just as this surplus will increase that we shall complete the canal without any one feeling the expense, and without stopping the regular increase of the dividends, exactly as has been the case at Suez. But, in order to open the Panama Ship-Canal to the navigation of large vessels before it is finally completed, the problem is to hold the water in the parts of the canal not yet dug to the requisite depth in what engineers call upper basins ("biefs supérieurs"); to hold the water there, and at the same time allow ships to pass in and out of these basins, we shall have, to construct metallic doors as for locks, like those seen in all harbors where there is a rise and fall of the tide, and in ocean harbors. Mr. Eiffel, at my request, is to take charge of this work, for which his experience, his scientific knowledge, and the great works of this kind he has undertaken and always succeeded in, naturally pointed him out beforehand as my assistant. That is the whole story. So, it is the future tide-level ship-canal at Panama that will continue to be dug; it will be laid out in a way to accommodate the traffic of the world, and be continued and completed much sooner than is supposed, although the traffic of seven and a half million tons calculated by the International Congress is actually more than ten million tons. The profits will soon be great enough to enable the canal to be finally completed with little delay, and at no further expense, as it will pay for itself."
Opinions about the Mound-Builders.—In explaining the methods of the Bureau of Ethnology in mound-exploring, Dr. Cyrus Thomas mentions three plans on which the work might be done that are worthy of consideration. The first is the systematic plan, under which all the ancient works should be surveyed and mapped, and then thoroughly explored and investigated; the second is the local plan, which begins with a limited locality and confines operations to it until the investigation of it is completed; and the third is the comprehensive plan, or plan of general study, in which the chief objects are to search for and study the various forms and types of the works and minor vestiges of art, and to mark out the different archæological districts as disclosed by investigation. This plan permits the carrying on of operations at various points simultaneously, or removal from place to place as the types and forms of a section are satisfactorily determined. The first of these plans is regarded as the most systematic and scientific, and the second as next so. Yet circumstances have made it expedient for the Bureau to adopt the third, which promised to yield the results that were most immediately demanded, more expeditiously and at less cost than the others. The question most prominently kept in view was that whether the mound-builders were Indians. From the data so far obtained, the conclusions appear to be justified that the mound-builders, in the area to which especial attention has been given, consisted of a number of tribes or peoples bearing about the same relation to one another and occupying the same culture status as the Indian tribes inhabiting the country when it was first visited by Europeans; that nothing trustworthy has been discovered to indicate that these tribes belonged to a highly civilized race, or that they were a people who had attained a higher culture status than the Indians; that the links discovered directly connecting the Indians and mound-builders are so numerous and well established that there should be no longer any hesitancy in accepting the theory that the two are one and the same people; that the statements of the early navigators and explorers as to the habits, customs, circumstances, etc., or the Indians when first visited by Europeans, are largely confirmed by what has been discovered in the mounds and other ancient works of our country; that the evidence obtained appears to be sufficient to justify the conclusion that particular works and the works in certain localities are to be attributed to particular tribes known to history; that the testimony cf the mounds is very decidedly against the theory that their builders were Mayas or Mexicans; and that evidences of contact with Europeans are frequent and authentic enough to make it probable that a goodly number of the mounds were built subsequently to the discovery of the continent by Europeans.
Some Advantages of a Fruit-Diet.—"Fruit and Fruit-Culture, as related to Health," was the subject of an address by Professor H. W. Parker before the Iowa State Horticultural Society, in which working among fruit and living with it are commended to a population who become bilious on excess of meat. In temperate zones, the author says, "the dire experience of almost universal disease, and the evidence of those who have freely used fruit, point to this as a most needful article of diet; and when we come to the tropics we find that men must confine themselves mostly to fruit-diet, a practice that should be largely followed in our long, hot summers; yes, with our present habits of unwholesome living, especially in respect to confined air and cooking, must be observed in winter as well. In the warm temperate climates there are enough examples of muscular, long-lived people who live on a minimum of animal food, such as those of the Grecian Archipelago, who subsist on goat's milk, figs, and maize-bread. Individual examples are to the same effect. Dr. Winship began as an invalid, and by athletics and diet attained such vigor that he could lift twelve hundred pounds. He indulged, we are told, occasionally in sardines, and for the rest depended on fruit and farinaceous (that is, starchy) food. The recovery of health in grape-cures shows what may be sought in that direction; the peach-cure has lately come into notice, and doubtless any ripe, fresh, juicy fruit, if not of a kind too astringent or laxative in certain cases, would do as well. I can testify that a quart or two of strawberries, twice or thrice a day, soon recovered me from torpidity of the liver and consequent constipation, increasing for a year or two; and yet this is spoken of as not of an aperient sort. Since then my only medicine is fruit the year round."
Thrifty Habits of a Woodpecker.—Not many observations have been recorded of the laying up of food for future use by birds. One woodpecker, in California, is known to deposit food by digging holes in the trunks of trees and driving acorns into them till the trunks look as if they were studded with brass nails. Professor O. P. Hay observed a similar trait in the redheaded woodpecker during an unusually favorable season for beechnuts in Indiana. "From the time the nuts began to ripen," he says, "these birds appeared to be almost constantly on the wing, passing from the beeches to some place of deposit. They have hidden away the nuts in almost every conceivable situation. Many have been placed in cavities in partially decayed trees; and the felling of an old beech is sure to provide a little feast for a bevy of children. Large handfuls have been taken from a single knot-hole. They are often found under a patch of the raised bark of trees, and single nuts have been driven into cracks in bark. They have been thrust into the cracks in front gate-posts; and a favorite place of deposit is behind long slivers on fence-posts. I have taken a good handful from a single such crevice. . . . In a few cases grains of corn have been mixed with beechnuts, and I have also found a few drupes, apparently of the wild-cherry, and a partially eaten bitter-nut. The nuts may often be found driven into the cracks at the end of railroad-ties; and, on the other hand, the birds have often been seen on the roofs of houses, pounding nuts into the crevices between the shingles. In several instances I have observed that the space formed by a board springing away from a fence-post has been nearly filled with nuts, and afterward pieces of bark and wood have been brought and driven down over the nuts, as if to hide them from poachers. These pieces of bark are sometimes an inch or more square and half an inch thick, and driven in with such force that it is difficult to get them out. In one case the nuts were covered over with a layer of empty involucres. Usually the nuts are still covered with the hulls; but here and there, when the crevice is very narrow, they have been taken off, and pieces of the kernels have been thrust in."
Alaska and its Tundra.—A contributor in the "American Field" describes Alaska as having dimensions not only in latitude and longitude—"for not a great distance from the Aleutian Islands, separating the Pacific from Behring's Sea, and in the former body of water we have the deepest sea-soundings known to science, while Mount Saint Elias cleaves the clouds for 19,500 feet, the highest mountain of the North American continent, and the highest Alpine peak in the whole world; for the line of perpetual snow and ice starts at its very base and covers it throughout except where buttresses of bare rock and pinnacles of perpendicular stone jut through the frozen mass, because they are too steep for the snow and ice to rest upon. . . . If we look at a map of Alaska we will see that fully a third of it is above the Arctic Circle, and the climate and other characteristics of this part are truly Arctic. The thermometer falls so low in winter-time that even the short, squatty Eskimo does not have to crane his neck to read the scale; the ground is frozen for numberless feet below the surface, while nothing grows on that surface except the hardy polar mosses that form the marshy covering for the vast tundra for which the Arctic flatlands are so well known. This marshy condition is produced every Bummer by the deeply-frozen ground t-hawing but a foot or two under the never-setting sun of that season, the deeper strata of ice remaining to act as an impervious shield to prevent the water from draining through, and on the prairies it remains as ice-water, surrounding the hardy mosses that thrive in it, and into which a traveler will sink up to his knees in the worst parts. A few stunted willows grow along the sluggish streams, but otherwise everything is bare of all except the moss. On this moss graze many herds of reindeer that roam with the wind and migrate backward and forward with the seasons." These reindeer furnish the Eskimos of the north and the Indians of the Yukon River with their meat and warm clothing.
Iridescent Clouds.—Mr. J. C. McConnel has studied the phenomena of iridescent clouds at Saint Moritz, Switzerland, where they are very common in winter, occurring usually whenever there are scattered clouds near the sun. Within a circle of about 2° radius, he says, the clouds are white, faintly tinged with blue. This space is surrounded by a ring of yellow or orange. The region of most vivid hues is comprised between 3° and 7°, and the most striking tints are purple, orange, green, and red. These colors are not arranged in rings, but are distributed over the thinner parts of a cloud in irregular patches. Beyond this region the only colors visible are green and red, which become fainter as the distance from the sun is increased. The author has detected them in a few cases at a distance of 21°. At some distance from the sun the greens and reds are frequently arranged in bands parallel to the edge of the cloud. The author supposes these colors to be the result of diffraction of light by fine particles of ice. The particular color assumed by any part of the cloud is determined by the distance from the sun and the average size of the particles. The particles are supposed to be in the form of thin hexagonal prisms, that being the shape among the known forms of ice-crystals best adapted to produce diffraction. Mr. McConnel calculated the probable diameter of the filaments, and found it to be between ·017 and ·009 millimetre for the purple, ·021 to ·010 millimetre for the orange, and 014 to ·009 millimetre for the blue. The absence of the colors from clouds composed of water particles is accounted for by the want of uniformity of size in the water-drops.
Accumulations of Atmospheric Dust.—Ruins of ancient cities and buildings are nearly always found wholly or partly buried. The material with which they are covered has been supposed to originate in the débris of buildings that have been erected and human works that have been going on upon their sites, but this can not always, or seldom wholly, be the case; for the same fact appears in desert and wilderness sites. Much is possibly due to superficial disintegration and the work of vegetation; but still another factor, more effective than has heretofore been supposed, may be sought in the deposition of atmospheric dust. In a note on this subject, read by him before the Geographical Society of Paris, M. Violet d'Aouest referred to Richthofen's account of a vast aërial formation of loess in China, and described his own observations in Mexico, where he found on the flanks of the highest mountains argillaceous strata not deposited by waters nor by the decomposition of the rocks; but investigation showed that they were produced by dust raised by the winds from the plains and deposited on the hills. These deposits varied from one hundred feet to—in some places—more than three hundred feet in thickness. They grow finer and finer as the height increases, and cease at the limit of vegetation.
Results of Nerve-Shock.—Many persons who experienced the earthquake in the Riviera have since suffered seriously from nervous shock, although they did not at the time appear to be greatly disturbed. This indicates that more injury may be done to the nerves by an undue excitement than is perceived at the time. The nerve-centers may, as an English medical journal suggests, be likened to batteries, and regarded as apt to be discharged suddenly and sometimes unconsciously; and when once their residual stock of energy is consumed, it can be restored only after a long time and by the exercise of extreme care. It is practically observable that whoa nutrition is impaired in a nerve-center or branch, extreme difficulty is met in restoring the integrity of the nervous function, and even the wear and tear cf ordinary life seems to increase the exhaustion instead of reducing it by stimulation of the recuperative faculty.
Handiwork-Teaching in Swedish Schools.—Slöjd is the Swedish name for handiwork instruction in the schools. It was invented by the famous Finnish educator Uno Cygnæus, and was adopted in Sweden about fifteen years ago. The teaching is confined to simple work in woods, if it is regarded merely as a training for the faculties, or in many branches if it is to be regarded as subsidiary to technical instruction. No efforts are spared to make the system attractive to pupils and parents. Pupils arc allowed to keep what they have made, or to buy it cheaply; or are credited with deferred pay, which they forfeit if they leave before a stipulated course is completed, or which is given them as credits in a bank-book on finishing the course. The sympathy of parents is catered to by teaching the children to make and use such common implements as are most in demand at home; and by allowing them the use of the school-tools to make family repairs. The system has proved very successful in Sweden, Norway, and Finland.
Protection of Building-Stone.—All methods of protecting building-stone against decay depend upon filling the pores of the stone with some substance that shall exclude water, the vehicle by which acids are introduced. This is easily done while the builders are handling the stone, but it is very hard after the structure has been set up to paint on the water-proof material so as to insure its absorption to any considerable depth. Several processes including the use of silicate solutions have been described by Mr. W. G. Dent as having been used with more or less of success. Oxalate of alumina applied to limestones gives them a coating of the insoluble double oxalate. Organic substances like linseed-oil give considerable protection for a time, but are ultimately oxidized. Among inorganic or mineral substances paraffine has been used, as upon the obelisk in Central Park, with a degree of success; but the objection holds against its application that the stone has to be warmed to secure a sufficient depth of absorption. The obelisk on the Thames Embankment, London, has been treated with a preparation of solution of gum-resins in petroleum spirit. But, Mr. Dent says, "if care be taken in the selection of the stone, it is only under special and exceptional circumstances that it will be considered desirable to resort to methods of preservation which must necessarily be expensive, and can only be regarded as the best cure for defects that admit of no other remedy."
The Wild Cattle of New Zealand.—The New Zealand farmers lost great numbers of cattle during the Maori wars which ended in 1868, through their being turned loose by the enemy and by other accidents incident to a season of disorder. These animals and their descendants now roam wild in the bush, particularly on the North Island, where they afford a sport "that is little less exciting and dangerous than that which exists in South Africa and the Western prairies of America." They are exceedingly difficult to reach, on account of the character of the bush around which they hover, which is composed of the long, twining creeper known as "supple-jack." No horse will try to penetrate this bush, because the instinct of the animal tell.? him that he will get his feet and legs entangled in the vines. "Not so, however, the wild cattle; they will, when surprised, rush madly into the densest shrubbery, and seem fully aware that nothing can possibly follow them into it; and it is thus that instinct has induced these cattle to bid defiance to man, and to live their primitive life over again."
Various Kinds of Soap.—According to a lecture by Dr. Stevenson Macadam, the remains of a well-organized soap-factory have been found in the ruins of Pompeii. Soap-factories existed in Italy and Spain in the eighth and in France in the ninth centuries. The manufacture in Great Britain is first heard of in the fourteenth century. White soap is generally prepared from tallow, with a little lard and palm-oil. In yellow soap resin is added. Soft soap is prepared from fatty substances, with potash. Cocoanut-oil soap has the advantage of being usable with sea-water, and is often called marine soap. Carbolic-acid soap contains about two per cent of carbolic acid, and has antiseptic as well as washing properties. In toilet soaps, as in old brown Windsor, when they are kept for a long time, the soda is influenced by the air and has its strong properties neutralized. Then it is remelted and stored up again, and remelted a second time, when it becomes soft and tender; but the toilet soaps of the present are not always given time to age. Pears's soap is ordinary soap of good quality, cut into shavings, dried, and treated with alcohol. The alcohol evaporates and leaves the transparent soap. The treatment has the effect of taking all the free soda out of the mixture.
Genesis of "Original" Rocks.—Dr. T. Sterry Hunt gave, in the British Association, a concise account of his theory of the genesis of the various groups of original or non-clastic rocks, which he classifies on the basis of their geognostic relations as indigenous, exogenous, and exotic masses. The superficial portion of a cooling globe, consolidating from the center from a condition of igneous fusion, he conceived to have been the protoplasmic mineral matter, which, as transformed by the agencies of air, water, and internal heat, presented a history of mineralogical evolution as regular, as constant, and as definite in its results as that seen in the organic kingdoms. The author next considered the conditions of softening and displacement of indigenous rocks, which permitted them to assume in many cases the relations of exotic rocks, and to become extended after the manner of lavas, as seen in the case of trachytes and many granite-like rocks. Such masses he designated pseudo-plutonic.
Efficiency of Explosives.—It is pointed out by Professor Charles E. Munroe, in his "Notes on the Literature of Explosives," that the theoretical efficiency of an explosive "can not be realized in useful work for several reasons, viz.: because of incomplete explosion; because of the compression and chemical changes induced in the surrounding mineral; because of the energy expended in cracking and heating rock which is not displaced; and because of the escape of considerable quantities of the gases through the blast-hole and the fissures made by the explosion. In all probability the extent of these losses can never be determined by direct experiment, as the phenomenon of an explosion does not admit of a close observation; nor can it be determined by comparison with the work done under other circumstances, as we are as yet uncertain as to the so-called dynamic resistance of rock. The useful work of a blasting charge is employed partly in shattering the rock and partly in throwing or displacing the shattered masses. It is a familiar engineering problem to reduce the projectile force of a blast to a minimum by means of suitable sized charges, properly located in blast-holes of estimated dimensions, and so avoid the cannonading of which workmen are fond. With the discovery of at least approximately correct values for the useful work of charges, we are now able to demonstrate the correctness of this principle."
Mistakes in treating Organic Refuse.—Most of the shortcomings of modern sanitary methods, says Dr. G. V. Poore, are due to the fact that, in our dealing with organic refuse, we commit a scientific error—i.e., we pursue a course that is in opposition to natural law. This error consists in mixing organic refuse with water. It then undergoes changes which differ widely from the changes which it undergoes when mixed with earth. According to Wollny, the process of oxidation of organic matter and the formation of nitrates take place most readily when a moderate amount of moisture is present, and the most favorable amount is about thirty-three per cent. When water is in excess, the amount of free oxygen is insufficient to favor the growth of mold-fungi, the schizomycetes (bacteria and micrococci) are formed, and, in place of oxidation, putrefaction occurs, with the formation of ammonia, free nitrogen, carbonic acid, and carbureted hydrogen. This process of deoxidation takes place in mixtures of putrescible matter with water, and takes place also, it is said, in soil which is thoroughly soaked in sewage. In the face of these facts, it is not to be wondered at that "sewage farming" has not proved a commercial success. We must, indeed, be in doubt whether, when the circumstances are more than usually unfavorable, it exercises any very great purifying action upon the putrescible mixture. In the treatment of putrescible refuse we have to aim at nitrification rather than putrefaction, and it is certain that by mixing with water putrefaction is encouraged and nitrification delayed. It seems to be almost incontestable that the proper course to pursue with regard to organic refuse—putrescible matter—is the very reverse of what we do pursue. We clearly ought to encourage oxidation and make putrefaction impossible. Putrefaction is certainly a great cause of ill-health. The putrefaction of organic refuse when mixed with water has, Dr. Poore thinks, been the chief cause of the development of modern sanitary progress—that is, of the need of doing something. Our forefathers were not given to this method of treating putrescible matter. House-slops trickled along open gutters, and excremental matters were deposited in dry pits.
Cameo-cutting for Amateurs.—Mrs. Henry Mackarness, in her "Young Lady's Book," represented cameo-cutting as an art simple enough to be acquired without great difficulty, which would "give young ladies a new and elegant pursuit." Only two kinds of tools are used, which are named the scawper and the spit-sticker. The work is performed at a bench or table, furnished with suitable gripping apparatus, the shell being fixed with setter's cement on a stick, which may be made of a five-inch section of a broom handle. Care should be taken to select a piece of shell without a flaw. Beginners should choose tolerably smooth pieces; but practiced workers prefer those which are irregular in their surface, because they furnish more scope for the exercise of skill. In cutting these the design follows the convolution of the shell. Care must be taken in cutting not to let the ground show through; but a skillful cutter will so arrange his design as to produce the blush of the ground in such portions as to enhance the value of his work. Shells are further liable to the faults of displaying crooked lines in the cutting, which are believed to have been the work of worms in the earlier stages of their development, and of "flaking." Beginners will draw the figure before attempting to cut; but a skillful operator will cut away at once, and rough out the head and face of a portrait very quickly. A workman can cut a portrait from a photograph in a few hours. The beginner should not spend more than two hours at a single sitting. In beginning, the learner should cut a few simple outlines, such as are furnished by the rose, the lily, or the fuchsia; the hand soon becomes accustomed to the use of the tools, and the timid cut becomes exchanged for the vigorous and graceful stroke of the artist. Great care is necessary in working the shell so as not to cut into the ground, on account of the extreme difficulty of removing any marks. Marks are removed by the use of powdered pumice-stone and water, applied on a piece of pointed wood; the next process is to smooth the surface with pumice-stone and oil; wash with a soft brush and warm water, then polish with the dust of the rotten-stone and sulphuric acid, mixed to a paste, and applied on the point of a piece of wood.
Vaccination and Erysipelas.—A report by Dr. Airy, on three cases of so-called fatal erysipelas after vaccination, will help in forming a judgment of the sort of foundation on which the fears of an outcome of this character rest. The three children were vaccinated by three different practitioners. In the first case the erysipelas set in too late for it to be possible for vaccination to have had anything to do with causing it; in the second case the child was surrounded with erysipelas in the surgery where it was brought to be vaccinated; in the third case no definite source of erysipelatic infection could be discovered, but the child lived in a low-lying place, close to swampy and unhealthy meadows. Thus, none of the cases were traceable to the vaccine lymph; and its innocence is attested by the fact that other children were vaccinated with the same lymph without the occurrence of untoward symptoms. The question arises next as to the degree of danger of erysipelas entering the vaccination-scratch, or the wound left by a ruptured vesicle, the same as it might any other wound. According to statistics presented by Dr. Buchanan, the proportion of such accidents that occurred in England and Wales during 1883 was 51 infants dying of septic disease out of 763,192 vaccinated.
Lime-Salts in the Food and the Teeth.—Dr. W. D. Miller, of Berlin, has been making experiments to determine how far changes can be produced in teeth by the presence or absence of lime-salts in food. His method is to extract a tooth from a healthy dog, and then to feed the animal upon food containing but little lime-salts for three months; then to remove a second tooth, and change the food to one containing an excess of salts. After four months o-f this treatment another tooth is extracted. The author has found that an appreciable loss of lime-salts occurs in the first stage, which amounts in one case to more than one per cent, and that the proportion of lime-salts rises again to normal during the second stage.
The Making of Britain.—In studying, by geological evidences, the changes which have taken place in Great Britain since it was first inhabited by man, Professor Archibald Geikie goes back to the time when it was not yet an island, but formed a part of the European Continent. Its separation occurred by gradual subsidence, in which the chalk ridge between Dover and Calais was the last landmark to disappear; and "along this narrow ridge the earliest Celtic immigrants may have made their way." It was probably finally washed away as much as sunk. At the dawn of history, the general appearance of the country must have been characterized by wide-spread forests, abundant bogs and fens, and a profusion of lakes; and at the first coming of the Romans the greater part of the country was probably covered with wood. Large tracts of these woods persisted for many hundred years, and as late as the twelfth century the woods to the north of London swarmed with wild boars and wild oxen, and the woods everywhere were the resorts of broken and desperate men. In the course of generations the wood and open land have largely changed places. The belts of clay soil, originally the most heavily timbered tracts, proved admirably adapted to agricultural purposes and were cleared for cultivation, while the open places, with their light soils, were abandoned, to become wastes of scrub and copse wood. Great topographical changes have been wrought by the disappearance of the fens and bogs. Some have been naturally silted up, and others have been artificially drained; which their sites are still indicated by such Saxon names as Bogside, Bogend, and Mossflats; and by the black, peaty soil which marks where they once lay. No one would be led to suspect by the examination of modern maps the number of lakes that once dotted the north of England and Scotland; but inspection of old maps will show many sheets of water that do not now exist, or are much reduced in size. Topographical names will reveal the sites of other and sometimes still older lakes, while geological evidence will tell of others of which there is no human record. Other changes have been and are going on along the shore, where the land is washed away at some places and added to at others. All these things are subjects for profitable study, and call for it; and we may add that similar changes are going on and invite attention in the United States. Their progress is much more rapid than any one could suppose till he begins to make it the subject of careful observation.
The Ruby-Mines of Burmah.—The ruby-mine tract in Burmah, according to Mr. G. Skelton Streeter's description in the British Association, is a large valley some twelve miles long by eight miles broad, and composed of several small valleys, or rather basins. It lies on the slope of the Sibwee Doung, which divides the Irrawaddy and Salwen Rivers. The valley bears signs of volcanic origin. The mines are of three distinct kinds. The first is furnished by the metamorphic rock, whose mass is traversed in all directions by huge fissures, caused probably in the past by shrinkage. These fissures are filled with a soft, clayey earth, generally containing rubies. At present they are worked in a very superficial manner. The mines of the second variety are on the sides of these rocky hills, where diversified strata of clayey consistency have been upheaved. The natives wash this earth slowly away by hydraulic mining. The third system of mining is by sinking pits in the lower or plain parts of the valley, and washing the earth extracted by band.
Effects of an Earthquake.—A paper was read in the British Association by Dr. T. Sterry Hunt and Mr. J. Douglas, describing their observations of the effects of an earthquake which took place in Sonora, Mexico, on May 3, 1887. The authors found the results of the undulatory movements of the soil apparent in the San Pedro and Sulphur Spring Valleys in great numbers of cracks and dislocations. For distances of several hundred feet, sometimes with a generally north and south course, vertical down-throws on one side of from one foot to two feet were seen, the depressed portion rising either gradually or by a vertical step to the original level. Branching, and in some cases intersecting, cracks were observed. These depressions were evidently connected with outbursts of sand and water, which, along cracks—marked by depressions on both sides—sometimes covered areas of many hundred square feet with layers a foot or more in depth, marked here and there by craters, two feet in diameter, through which water had risen during the outburst of these volcanoes.
Agassiz's Service to Evolution.—Professor Le Conte's ascription to Professor Agassiz of the credit of having laid the basis for the doctrine of evolution is confirmed, from a different point of view, by Professor Alfred Newton, in his opening address before the Section of Biology of the British Association. The speaker, referring to Agassiz's doctrine of centers of creation, said that "creation in his mind was no figurative expression. lie meant by it. . . a direct act of God—in other words, his belief was, that there had been going on around us a series of mysterious performances, not one of which had ever been consciously witnessed by a human eye, each of which had for its object the independent formation of a new living being, animal or plant." This doctrine of a continuous series of miraculous acts having gone on for an indefinite time was perfectly logical when the premises were admitted; and it became obvious that the alternative was between that doctrine and the theory of transmutation of species. The having made this thought clear is declared by Professor Newton to have been a great service rendered to the new theory by one who was its most determined opponent.
A Floral Moth-Trap.—Mr. Robert E. C. Stearns, in the "American Naturalist," describes the plant Araujia albens as a "mothtrap." The plant, formerly called Physianthus, is a native of Buenos Ayres, but has been pretty widely distributed in the United States, and may be found now at places as far apart as Boston and San Francisco. The insects are caught in the flower, which is trumpet-shaped, flaring at the mouth, where the petals divide, and then uniting and forming a tube, which is swollen into a bulbous form where the corolla joins the calyx. The stamens are furnished with side wing-like processes and exterior spurs, which press against the gymnecium, and hide the ovaries and pollen-masses. "The moth, in pursuit of the nectar, first reaches that portion contained in the pockets between the bases of the spurs; then, in search of more, having already thrust the proboscis down the tube of the flower, describing a curve between the exterior of the stamineal crown or mass and the inside of the bulb of the perigonium, it has to push the proboscis upward in order to reach that portion of the flower where the anther-cells, pollen-masses, and glands are in close juxtaposition." Having satisfied its hunger, or otherwise, upon attempting to withdraw the proboscis by a direct pull—which it can not do, because the organ is not provided with any muscular arrangement by which the curved motion made in entering can be reversed—the proboscis "becomes wedged in between the edges of what may be termed the anther-wings, or rather the edges thereof, and is held tight, very much in the same way that an old-fashioned boot-jack grips a boot. The more the moth pulls, the tighter or firmer the grip, and escape is impossible, unless the flower has reached such a degree of maturity that its substance has become somewhat softened or wilted."
Disinfection by Heat and by Steam.—Dr. II. F. Parsons has found, in experiments on the disinfection of packages by heat and by steam, that dry heat at the boiling-point for an hour is sufficient to destroy active bacilli of all ordinary infectious diseases; but, if spores are to be attacked, a heat of 245° for an hour or of 220° for four hours will be required. The complete penetration of an object by steam-heat for more than five minutes is sufficient for its full disinfection; and this method is applicable to such articles as pillows, which are very difficult of penetration to dry heat. Moistening the air of the heated chamber diminishes the time necessary for penetration, while it also makes the distribution of temperature through the chamber more agreeable, and tends to prevent the scorching of articles placed in it; but it was not found to increase the disinfecting power at the temperature employed. Damage may be done to articles in disinfecting them by heat or steam, by scorching or partial de-composition of organic substances; by fixing of stains; by melting of fusible substances; by changes in color, gloss, etc.; by shrinking and felting of woolen materials; or by wetting. The nature of the articles should, therefore, be regarded in adapting the process to them.
English Taxes.—The first recorded tax imposed upon Britain was laid by Julius Cæsar, who, after his victories, required for Rome an annual tribute of men and wild animals—the men to be kept as hostages, the animals to be fought with in the arena. When ecclesiastical domination came in, the Pope levied a "Peter's pence" for the support of his English University at Rome. When the English conquered Wales, they levied on the people an annual tax of three hundred wolves' heads, which proved a great blessing to the principality. After England became exposed to great danger from the incursions of the Northmen, a land-tax of twelve pence per "hide" was levied in order to raise a sum with which to buy off the invaders. The consequence of this silly policy was that more invaders came to be bought off. A poll-tax was imposed in the fifteenth century of one shilling a year upon every person, except he belonged to the clergy, above the age of fifteen years. This was distasteful to the people, and led to rebellion. In another form of taxation, laborers and tradesmen were required to give their services to the king or to a noble. Many palaces, Windsor Castle among them, were built in this way. From 1695, for thirteen years, every person not a pauper was required to pay a tax for each child born to him, rising from two shillings in the case of a common person to thirty pounds in the case of a duke. A bachelor's tax of one shilling in the case of ordinary persons was imposed on unmarried men over twenty-five years old, and on widowers without children, but wealthy people and nobles had to pay more. By Queen Elizabeth's act of uniformity, persons who refused to become Episcopalians, or who absented themselves from church on Sunday.«, had to pay a tax of a shilling a year. Perhaps the most oppressive and impolitic taxes imposed by the British Government were those on windows and on funerals, with which even the history of this nineteenth century has been blotted.