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Popular Science Monthly/Volume 35/May 1889/Popular Miscellany

< Popular Science Monthly‎ | Volume 35‎ | May 1889


Preserving Timber from Moisture.—The following recommendations are given by the Forestry Division of the Department of Agriculture in regard to the cheaper coatings for keeping moisture out of timber: Never apply paint or any other coating to green or unseasoned timber. If the wood was not well dried or seasoned, the coat will only hasten decay. Good coatings consist of oily or resinous substances which make a smooth coat capable of being uniformly applied. They must cover every part, must not crack, and possess a certain amount of plasticity after drying. Coal-tar, with or without sand or plaster, and pitch, especially if mixed with oil of turpentine and applied hot (thus penetrating more deeply), answer best. A mixture of three parts coal-tar and one part clean unsalted grease, to prevent the tar from drying until it has had time to fill the minute pores, is recommended. One barrel of coal-tar (three to four dollars per barrel) will cover three hundred posts. Wood-tar is not serviceable because it does not dry. Oil paints are next in value. Boiled linseed-oil, or any other drying vegetable oil, is used with lead or any other body, like powdered charcoal, which will give substance to it. Immersion in crude petroleum is also recommended. Charring of those parts which come in contact with the ground can be considered only as an imperfect preservative, and unless it is carefully done, and a considerable layer of charcoal is formed, the effect is often detrimental, as the process both weakens the timber and produces cracks, thus exposing the interior to ferments. Lastly, in communities where durable timber is scarce, it will pay to establish a plant for impregnating timber with antiseptics by the more costly processes described in "Forestry Bulletin" No. 1.


Geological Progress.—In reviewing the progress made by geological science during the last twenty-four years, Prof. W. Boyd Dawkins mentions the advantages which it has drawn from microscopic analysis of the rocks, in the study of metamorphism, and of the crushing and shearing forces that were brought to bear on the cooling crust of the earth; and from deep-sea explorations, revealing the structure and deposits of the ocean abysses. From a comparison of these deposits with the stratified rocks, we may conclude that the latter are marginal, and deposited in depths not greater than one thousand fathoms, or at the shore end of the globigerina ooze, and most of them at a less depth—and that consequently there is no proof in the geological record of the ocean depths having ever been in any other than their present places. In North America, the geological survey of the Western States has brought to light an almost unbroken series of animal remains, ranging from the Eocene down to the Pleistocene age. In these we find the missing links in the pedigree of the horse, and sufficient evidence of transitional forms to enable Prof. Flower to restore to its place in classification the order Ungulata of Cuvier. These may be expected to occupy the energies of American geologists for many years, and to yield further proof of the truth of the doctrine of evolution.


Yucatan Hammocks.—With a couple of straight poles, a shuttle, a thin slab of zapoli-wood, and a pile of heniquen-leaves at hand, says Consul Thompson, of Merida, the Yucatecan is ready to accept contracts for hammocks by the piece, dozen, or hundred. The poles are placed a distance apart, according to the required length of the hammock. The thin slab of hard wood is fashioned into a stripper, by the aid of which the fiber of the thick heniquen-leaf is denuded of its envelope, and a wisp of rasped fiber is obtained. This having been bleached, the fibers are separated into a certain number, and these are rolled into a strand. Two or more of these strands are then taken out, and by a similar dexterous manipulation converted into a han or cord, from which the hammock is made. The cord is riven rapidly around the two upright poles, and the shuttle, worked by the women, seems to move and seek the right mesh, says Consul Thompson, with a volition of its own—and in a very short space of time the hammock is made and laid with its kind, to await the coming of the contractor. Almost the entire exportation of hammocks from Yucatan is absorbed by the United States. All the districts of the State produce hammocks, but that of Tixcoco more than all the other districts combined. Chemax hammocks are noted for their fineness, and do not have to seek a market abroad.


What is Fire-proof?—The idea that theatrical appurtenances of wood and cloth can be made efficiently fire-proof by soaking them with certain chemical solutions is, in the opinion of Mr. Walter Emden, a serious error. Theoretically, the soaking works beautifully, and in practice for a time secures immunity against the spread of fire. "But for how long? Of the majority of those preservative solutions, it is a question if anything is left at the end of a certain time. They evaporate or sublimate or pass off into the atmosphere. No one can say with any degree of certainty for what length of time a beam or a cloth will be fire-proof as the result of soaking in any non-inflammable solution. Now, miscalculations in respect to this may lead to the most terrible catastrophes." A further point of the greatest moment is that gas-flames raise the temperature of wood and canvas in their vicinity to 140° F., and dry them to tinder. Obviously, actual contact with a caked flame must, under such circumstances, produce results altogether different from those of the experiments usually made with preservative solutions. It is the materials themselves which are used in the construction that must be proof against fire. The aim should be, not to make some combustible material incombustible, but to use only fire-proof materials.


Bread of Water-Lily Seeds.—The seeds of various species of water-lilies form the food of thousands of people in Asia and some parts of America. The most important species for this purpose are those belonging to the genus Trapa, which are known in India as Singhara, in China as Ling, and generally as water-chestnut. The fruit of the Trapa bicornis, which grows in the lakes of China, is collected by women and children who paddle about among the plants in small circular boats resembling wash-tubs. Other species are grown in Cashmere, where the lakes become so crowded with the plants that navigation is made impossible, and the Government derives £12,000 a year from the taxes on the crop of a single lake; and in India, where the cultivation is systematically carried on. The fruit abounds in starch, which has the flavor of a chestnut, and may be eaten raw or cooked. The dried nuts will keep for many years. The meal may be made into cakes or into a porridge. If the kernels are soaked overnight in cold water, they will be ready in the morning to be boiled or steamed into food. The seeds of the lotus (Nelumbo) were much used as food in ancient Egypt, but seem to be neglected now. The tuberous roots resemble the sweet potato and are starchy. The root-stalks when boiled are farinaceous and agreeable, and those of the American species are employed as food by Western Indians. The seeds of the lotus, in India, are eaten raw when green, and roasted or boiled when ripe and hard. The 'root, which is two or three feet long, is eaten, boiled, as a vegetable. The Klamath Indians live chiefly on the tookow, or seeds of the yellow water-lily (Nuphar lutea). The capsules are broken, and the seeds are separated from their husks.


The Philosophy of Waist-Belts and Corsets.—In the course of an investigation upon the work of the heart in health and disease certain facts were observed by Prof. Roy and Mr. J. G. Adams which throw light upon the physiological bearing of waist-belts, etc. By means of a cardiometer, they register accurately the changes in volume of the heart and the amount of blood propelled by it, under varying conditions. In the dog, even a slight compression of the abdomen caused an increase in volume of the heart, and with this a greatly increased amount of blood, passed through the heart in a given time. These phenomena can be explained without difficulty. The abdominal vessels are capable of containing all, and more than all, the blood in the organism. Slight compression of the abdomen will, without disturbing the arterial supply, drive out from the abdominal veins and venous capillaries a large amount of blood; and this blood will be of use for the other regions of the body. Now, the functional activity of any organ depends directly upon its blood-supply. Increase the arterial blood-supply of any part, and, other things being equal, the activity and power of work of that part are increased. The abdominal walls in front and at the sides are formed of soft, elastic tissues. In health, pressure is, through these, exerted upon the abdominal contents, and at the same time upon the abdominal veins and venous capillaries, by means of the muscles contained in these walls. If, however, the muscles lose their tone, the walls become flaccid, and the veins dilate, and thus holding a larger amount of blood than is necessary, act as reservoirs for this blood, and so deprive the rest of the body of an amount of fluid necessary for its due nutrition. Here, then, we have an explanation of the use of some form or other of waist-belt by all nations who have passed beyond the stage of absolute barbarism. The waist-belt is of use, and has constantly been used, in cases of sudden and great exertion, and in those cases where it becomes necessary to counteract the tendency to a useless storing up of blood in the abdomen; and by persons in health, in bringing more blood into the service of the brain and muscles to produce a condition of increased mental and muscular activity. Flaccid abdominal walls are rather the rule than the exception with women, and among men occur in those leading sedentary lives. We are, therefore, brought to conclude that among women some form of waist-belt is advantageous. Moderate constriction does no harm; extreme constriction is absurd and dangerous.


The Scilly Islands.—Scillonians is what the inhabitants of the Scilly Islands call themselves. Though politically attached to Cornwall, and nearer to it than to any other part of the world, they are not Cornish, but of high-blooded English stock, being to a large extent descended from the Godolphins and from royalists who had suffered from the English civil wars. There are, however, considerable local differences between the people of the several smaller islands. lu the days of sailing ships the Scilly Islands were an important naval outpost and a place of refuge for vessels in stormy seasons. The people were skillful ship-builders and prosperous ship-owners. Steam has deprived them of most of their old advantages, and they have had to turn their attention to other pursuits. The mild climate and the good soil of the islands are favorable to all kinds of vegetation. Raising early potatoes and vegetables for the English markets has been a remunerative occupation. Recently the raising of narcissus and other bulbs has promised to be still more profitable, and the people are every year giving more and more attention to it. In 1887 more than a hundred tons of flowers were exported. The small extent of the islands bringing them into close relations, and almost inevitably under one another's eye, the Scillonians are quite sociable and considerably prone to gossip. They give occasional dinners, at which heavy cake and clotted cream are favorite dishes; but they object to dancing and card-playing, and abhor jesting and flippancy. They are great readers, and keep in the current of English periodical literature; and, having had George Eliot and Tennyson to visit them, they are "not to be awed by the prestige of any literary magnate." Finally, Mr. Frank Boufield says of them, "Most of them seem to have had a tradition of having come in from somewhere at no very remote period of the past, and I am very doubtful if there is any aboriginal population—that is to say, families who have no record or reminiscence handed down of having lived somewhere else."


Chemical Bibliographies.—The report of the American Association's Committee on Indexing Chemical Literature mentions as published, the "Provisional List of Abbreviations of Titles of Chemical Journals," Dr. A. Tuckerman's "Index to the Literature of the Spectroscope," and Prof. Clarke's "Table of Specific Gravities"; as completed, Prof. Traphagen's "Index to the Literature of Columbium," and Prof. Bolton's "Bibliography of Chemistry" for 1887; and as in preparation, indexes on "Ethylene," by Mr. A. A. Noyes; "Methane," by Prof. W. P. Mason; "Cæsium and Rubidium," by Mr. William Rupp; "Tantalum," by Prof. Traphagen; a "Bibliography of the History of Chemistry," by Dr. Bolton; and "Thermodynamics," by Dr. A. Tuckerman. Bibliographies are mentioned of "Food Adulteration and its Detection," by Dr. J. P. Battershall; "Milk," by E. W. Martin; and "Butter," adulterations, testing, etc., by Prof. Elwyn Waller and others. Among lists of patents relating more or less to applied chemistry are those of Mr. C. T. Davis on the manufacture of leather; of bricks, tiles, and terra-cotta; of paper; and his "Treatise on Boiler Incrustations"; and Mr. William T. Braunt's "Treatise on Animal and Vegetable Fats and Oils." B. Tollen's "Handbuch der Kohlenhydrate," Breslau, 1888, contains about fifteen hundred references to the literature of carbohydrates. Dr. A. B. Lyons is publishing, in the "Pharmaceutical Era," a monthly "Index Pharmaceuticus." The work of the committee is now being supplemented by chemists in Great Britain.


Old and New-Fashioned Ideas in Medicine.—Dr. Malcolm Morris has indicated some points in medical practice in which a mysticism, which was one of its predominant features in the middle ages, still lingers around it. "There remains in the people," he says, "a belief in the efficacy of drugs as drugs—a belief that, as for every bane there must be an antidote, so for every disease there must be a curative leaf or root. Nature is distrusted; disease is still represented as some evil influence to be exorcised. In the popular mind Disease walks the earth as a devouring fiend, and has a personality about it as of old. The phrases 'Stricken with disease,' 'visitations,' and 'seizures,' are survivals of the conceptions of primitive times. . . . The mysticism survives in the courtly phrase and the ambiguous language of the practitioner of modern times. When sorely pressed by the sick man, the physician's only armory is equivocation, from which he draws such verbal weapons as 'the state of the constitution,' 'the tone of the body,' 'the general health,' 'lowered vitality,' and all that kind. . . . Are these not in some sort a survival of the circle of the horoscope?" The profession is also at a disadvantage because of a skepticism, reacting from the implicit faith in drugs of the olden time, which repudiates all aids and accessories; briefly, it states its deliberate opinion that disease is infinitely better left to itself. The natural physiological energy of the body is the prime element in the healing process. This is neither more nor less than modern fatalism—waiting on events. Such a doctrine, if successful, would be fatal to medicine." A third evil under which it suffers is materialism, which "in medicine may be carried to an injurious extreme. In modern pathology, for example, as originated by the German school and taught by its apostles, while men are actively contesting as to the nature or formation of a certain cell—whether it be spindle-shaped, round, or ovoid; whether it be derived from this tissue or from that—they are likely to lose sight of the real bearings of the case. By all means respect facts, and you can not show better respect for them than by using them. A medical inquirer is not a mere collector. Collect your facts, and then reason from the data you have established. A collection teaches nothing till it has been arranged. The tendency at present is, in the majority of instances, to collect everything, and to arrange and therefore to adduce nothing."


Sanitary Science and Children's Health.—Among the greatest gains that have recently been made in sanitary science, Mr. Edwin Chadwick counts the power that has been obtained of preventing children's diseases. "In the larger district schools," he says, "the districts of the poor-law unions, the children's chief diseases are now practically abolished. These institutions may be said to be children's hospitals, in which children, orphans of the lowest type from the slums, are taken in large proportions with developed diseases upon them, often only to die from constitutional failure alone. Yet in a number of these separate schools there are now no deaths from measles, whooping-cough, typhus, scarlatina, or diphtheria. The general death-rate is about ten in one thousand, and of those who are not in the probationary wards, of those who come in without developed disease upon them, the death-rates are now less than three in one thousand, or less than one third of the death rates prevalent among the children of the general population of the same ages." In an institution where the old death-rate was twelve in one thousand, by drainage and clearance of sewage-smells the rate was reduced by more than one third; then, after improving the ventilation of the rooms and providing a separate bed for each child, the rate was reduced to less than three in one thousand, "and that with children of the lowest type. In a visit to one of these halftime schools, after an interval of several years, I was so struck with the appearance of the children as less pallid and with less of the dull, leathery look that I had seen before—they were bright and fresh-looking—that I observed to the manager that he must have had a new class of children since my last visit. His answer was 'No,' but that since the sanitary improvements had been made in the lower districts the children received from them were of the improved type which had struck me."


American India-Rubber.—The India-rubber of Central America is obtained from varieties of Castilloa, which yield rubber very little inferior to that obtained from the Siphonia. To raise India-rubber plants which are indigenous to one place in another where the conditions are at all favorable is no difficult task, but to make the same plant successfully productive is another matter altogether. Mr. Thomas B. Warren has called attention to the influence which handling raw rubber with sweaty or dirty hands has in promoting its decay. The less the raw article is fashioned by the hands in handling, the better. Grease of any kind, even in small quantity, is pernicious to the durability of the substance. When handled too much in manufacturing, it is sure to show signs of decay after a short time in the parts most exposed to manipulation. It makes a great difference in the quality of the raw product whether it has been collected by a relatively clean Brazilian Creole or by a fatty-perspiring African. When rubber shows signs of decay from this cause, dusting over with raw sulphur tends to arrest it.


Whisky no Antidote for Rattlesnake-Poison.—The popular opinion that whisky is an antidote to rattlesnake-bite is controverted by Dr. A. T. Hudson, of Stockton, Cal., on the authority of experiments by Dr. S. Weir Mitchell. Dr. Mitchell mixed the virus of the rattlesnake with alcohol and with other reputed antidotes, and found. on injecting the solution into animals, that its power was not altered. He found also that the effect of the virus was subject to very well defined limits, and that a quantity which would kill an animal of a certain size was much less powerful, or inert, upon larger animals. If a large snake should bite a goat of about fifty pounds' weight, and afterward two children of corresponding weight, he might kill the goat, while the children would survive, because not enough virus was left after the goat was bitten seriously to harm the children; then, if whisky were given to the children, their recovery would be attributed to it, while it really had nothing to do with the matter. It is rare that an adult person dies from the bite of a rattlesnake. Whisky may, however, be regarded as physiologically antidotal, in so far as it will sustain the flagging powers while the poison is being eliminated by the excretory organs.


The Teak-Tree.—Teak-wood is the most important of the forest products of Siam. It is used in immense quantities throughout the East for house-building, and is largely exported to China and Europe for ship-building purposes. It is said to be unsurpassed for resisting the ravages of the white ants and the effects of the weather. It grows in the northern part of Siam and Burmah at a height of 1,200 feet and more above the sea, and reaches its greatest perfection in about a hundred and twenty years; but a good-sized tree that can be cut down when quality of wood is not an object, can be grown in ten or fifteen years. The teak district is from 100 to 150 miles wide. The forests are in charge of the governors of the provinces in which they are situated. They are generally leased for a term of ten years, and the lessee is obliged to fell and remove the greatest number of logs possible, paying a definite royalty to the governor. The trees are girdled, and are left standing for two years to allow the sap to run out and the wood to become perfectly dry. The cutting down takes place in the dry season, and the logs are left until sufficient rain has fallen to allow of their being dragged to the river with the help of elephants. After the logs are made up into rafts, they are delivered to the raftsmen to convey to Bangkok; when all is ready, the evil spirits of the river must be propitiated, the cost of which is paid by the owner of the timber. This custom remains in force, despite the efforts of the foreign and educated classes to stop it, and should any one ignore it he would be unable to procure raftsmen.


Discovery by Observation.—The circumstances attending an archaeological discovery recently made in German Altenburg, on the Danube, illustrate in the most striking manner the value of intelligent observation. Prof. Hauser was interested for a month in watching the colors of an extensive cornfield, which varied in every part. He found an elevated post of observation, and, after a week's close attention, declared it to be his opinion that the corn was growing over the site of an ancient amphitheatre. His drawings showed that the oblong centerpiece was somewhat concave, and the corn was quite ripe in that part, because there was much soil between the surface and the bottom of the theatre. Elliptical lines of green, growing paler the higher they rose, showed the seats, and lines forming a radius from the center showed the walls supporting the elliptical rows of seats. Excavations were made as soon as the corn had been harvested, which confirmed the professor's theory in nearly every particular. At six inches below the soil the top of the outer wall was found, and from there the soil gradually grew thicker until the bottom of the arena was reached, the pavement of which is in perfect condition. From the theatre a paved road leads to the Camp of Camuntum.


The Buddhist Story of the Partridge.—Among the Buddhist stories which Mr. T. W. Rhys Davids has made known to the public is a legend of 400 b. c., pertinent to the question of the standards of precedence. It runs to the effect that a partridge, a monkey, and an elephant, friends, dwelling near a great banyan-tree, discussing which should be considered first, inquired which was the oldest among them. The elephant, when asked how far back he could remember, replied that when he was a little elephant he used to walk over the banyan-tree, and its topmost twig just grazed his belly. The monkey, when quite a little monkey, could gnaw the topmost twig of the tree as he squatted on the ground. But the partridge said: "Friends, there used to be another banyan tree. One day, after eating of its fruit, I voided a seed here. Hence this tree." So they agreed, the story continued, to honor and reverence the partridge, as he was the oldest, and he trained the others in obedience to the Five Precepts. Thenceforward they lived together in so beautiful a harmony that it became a proverb, and was known as "the beautiful life of the partridge." And they all three went, after death, to heaven. The story accords with the general idea among the ancients that the birds were of very old lineage.


Asphalt and Petroleum in Venezuela.—A part of the department of Colon, in Venezuela, is very rich in asphalt and petroleum. At one place a thick bitumen is ejected from the mouth of a cave, in globules which explode with considerable noise. The place called the infernito, or little hell, is a mound of sand, from twenty-five to thirty feet high, on the surface of which are numerous holes of different sizes, whence petroleum and hot water are ejected with a noise equal to that caused by two or three steamers blowing off at once. Considering the immense amount of inflammable gases that accompany such flows of petroleum, it is suggested that something of the kind may be connected with the Taro of Maracaybo—a constant lightning without thunder, which is observed from the foot of the bar at the entrance to the lake. Croppings of asphalt and coal appear at the foot of the mountains in the department of Sucre; and near the mountains is a flow of a black liquid, distinct from asphalt or petroleum, and apparently identical with a substance which occurs among anthracite deposits.


Habits of Turtles.—Turtles are described as sleepy creatures that rest at intervals throughout the day and become abnormally active at night. When asleep they lie upon the bottom of their habitat, with their heads downward and eyes closed, and are not easily disturbed. Their weight is considerable, and precludes theta from moving constantly in the water; and, as a rule, when swimming they keep near the surface, and stretch their heads out, in order to gulp in air readily. Upon land they are helpless, almost as powerless as the seal in a similar situation. They capture their prey with great agility, for, with their long necks, they can thrust their heads forward very rapidly. The head, fin, and tail are independent of the shell, and move freely, but can not be drawn wholly under the shell, like those of the tortoise. Turtles, especially young ones, are very pugnacious, and fight by striking their adversary's head with their fins and biting. Mr. Carter, of the British National Fish-Culture Association, thinks it practicable to propagate them artificially. The eggs should be placed in sand, heated from beneath by water-pipes to a constant temperature of 70° F., which could be raised in the daytime to 100° by concentrating the temperature from without. The young turtles will seek for water at once, and this should be provided, warmed to 100°. While propagation in this way might be profitable, it would not be easy to domesticate the animals to our cool latitudes.


Influence of Antiseptics on Foods.—It has become common in trade to apply antiseptics to perishable foods, in order to preserve them, salicylic acid being probably the most used. It is important to ascertain what the effect of the addition is upon the quality of the food, and upon the digestive functions. Lehmann has shown that salicylic acid does not usually contribute any injurious quality to food, but apprehends that the indiscriminate use of such substances may be dangerous. Experiments have been made in our Department of Agriculture to determine what effect in retarding digestion may be possessed by such substances as salicylic acid, boric acid, sodium acid sulphite, saccharine, beta-naphthol, and alcohol. It was found that salicylic acid prevents the conversion of starch into sugar under the influence of either diastase or pancreatic extract, but does not very seriously interfere with peptic or pancreatic digestion of albumen. Saccharine holds about the same relation as salicylic acid. Sodium acid sulphite and boric acid arc practically without retarding effect. Beta-naphthaline interferes decidedly with the formation of sugar by diastase, but not with the action of pancreatic extract on starch. Peptic and pancreatic digestion of albuminoids were almost prevented by it. The experiments show that the indiscriminate use of these agents, without sanitary inspection, should not be allowed.


Bells as Weather Indicators.—M. P. J. de Ridder, of Lebbeke, Belgium, has observed that bells are heard further away when the atmosphere is in cyclonic motion, and that a calm atmosphere, saturated with moisture, favors the transmission of sound, while contrary winds are not always an obstacle. Certain small bells six and eight kilometres southeast from Lebbeke are called water bells by the people there, because their being heard at Lebbeke is immediately followed by a season of rain. And, generally, the hearing of a distant sound, like that of a bell or the rumbling of a railway train, is regarded as portending the end of fine weather and the approach of rain. One bell, which is ten kilometres away, is heard twice a year—in March or April, and in September or October—and always in identical conditions of the sky.