Popular Science Monthly/Volume 14/February 1879/Popular Miscellany

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POPULAR MISCELLANY.

Reorganization of the Government Surveys.—We have already briefly stated the conclusions reached by the Committee of the National Academy of Sciences, appointed to consider what changes might be desired in the method of conducting the surveys of the Territories. We have since received an official copy of the Committee's report, and consider its subject matter of sufficient importance to justify a fuller abstract. The Committee interpreted the act of Congress directing their inquiry as applying only to surveys of the public domain, and hence did not take into consideration surveys or investigations which have for their objective point engineering works: such surveys, in the judgment of the Committee, should be conducted by the engineer corps of the army. The surveys which, in their opinion, were intended by the act to be inquired into were those popularly known as Wheeler's, Hayden's, Powell's, and the Land Surveys under the supervision of the Land-Office. Besides these, though not enumerated in the law, there is the Coast and Geodetic Survey. All the work done by these different corps may be classed under two heads: 1. Surveys of mensuration; 2. Surveys of geology and economic resources of the soil. The surveys of mensuration are at present conducted by five independent organizations, already named. There is no coördination between these five surveys, and their results show many contradictions. The geographical work of Wheeler's, or Hayden's, or Powell's survey is of little value for the parceling of land, while the land surveys are of correspondingly slight topographical and geographical value. The opinion of the Committee is, that "the Coast and Geodetic Survey is practically best prepared to execute the entire mensuration system required." But the Committee recommend that this survey be transferred from the Treasury to the Department of the Interior, and that in addition to its original field of work it should also assume the entire mensuration of the public domain.

The Geological Survey should have a separate organization. "To meet the requirements of existing laws in the disposition of the agricultural, mineral, pastoral, timber, desert, and swamp lands, a thorough investigation and classification of acreage of the public domain are imperatively demanded. The Committee, therefore, recommends that Congress establish, under the Department of the Interior, an independent organization to be known as the United States Geological Survey, to be charged with the study of the geological structure and economic resources of the public domain." And the Committee recommends a discontinuance of the present Geographical and Geological Surveys and the present Land Surveys. "The effect of the above changes," says the Committee, "will be to maintain within the Interior Department three distinct organizatians: 1. The Coast and Interior Survey, whose function will embrace all questions of position and mensuration; 2. The United States Geological Survey, whose function will be the determination of all questions relating to the geological structure and natural resources of the public domain; 3. The Land-Office, controlling the disposition and sale of the public lands, including all questions of title and record. With this division should be secured a perfect coördination and coöperation between the three branches. The Land-Office should call upon the Coast and Interior Survey for all surveys and measurements required for the sale and disposition of land. The Land-Office should also call upon the United States Geological Survey for all information as to the value and classification of lands. The results of all the mensuration surveys, as soon as completed, should be immediately available for the Land-Office and for the Geological Survey, and for other branches of the Government as required. The Geological Survey should be authorized to execute local topographical surveys for special purposes, such, for instance, as the subterraneous surveys of mining districts and metallic deposits, etc."

 

Huxley on the Hand.—Professor Huxley chose for the subject of a recent lecture at the Workingmen's College, of which he is President, the human hand. He looked on the hand as not second in importance even to the brain itself. He pointed out the great diversity of operations for which man is dependent on the hand, and observed how it performs all its important functions by virtue of certain very simple facts in its form of construction. He referred to that famous work, Paley's "Natural Theology," and the argument which it enforces—that if a person were to find the whole machinery of a watch he must needs infer from the works of it that it must have been intended to serve a certain purpose. But Professor Huxley pointed out that, whatever the force of the argument of analogy in the case of the hand, it most assuredly does not apply in the sense in which it was used by Paley, because it can easily be shown that a man's hand was not put together in that way, but that it came about in quite a different manner. It was not a process in any way analogous to human means of construction, being, in fact, as different from the latter as the taking of a piece of iron and making it into an engine differs from taking it and letting it grow to an engine. This difference, he remarked, is highly important, as showing the danger of arguing from mere analogy—it shows that Paley's argument is not consonant with fact. Paley could not conceive that so complicated a structure as the human frame might, as a matter of fact, be developed or evolved by a purely natural operation.

 

Vehicles of Malaria.—Ague is commonly supposed to be due to the entrance into the system of a miasmatic organism. But no microscopist has ever seen this organism, neither can we account for the intermittency of the ague-paroxysms, nor can we say for certain through what medium it finds an entrance into the system. The majority of writers hold the opinion that the air of marshes is the sole cause of intermittent fever. But there exists strong evidence going to show that water, too, is a carrier of the poison. Take, for instance, two or three cases cited in the "Lancet"; and, first, the case recorded by Boudin, of three vessels sailing from Algiers to Marseilles, conveying eight hundred soldiers, who on shore had all been exposed to the same atmospheric conditions. Two of these vessels were supplied with good water, but the third with water from a marsh. The two former arrived at Marseilles without a sick man, but the third ship lost thirteen men, and had one hundred and twenty sick, ninety-eight of whom were affected with malaria. Again, there is the outbreak of ague at Tilbury Fort in 1872, cited in Parkes's "Hygiene," where thirty-four men out of a garrison of one hundred and three were seized with ague, while the people at the railway station and the coast-guard men and their families just outside the fort entirely escaped. The troops had been supplied with water stored in tanks, collected from the rain-water of the roofs, while the people outside obtained theirs from a spring, the atmospheric conditions in both cases being identical.

 

The Werdermann Electric Light.—Mr. Edison's announcement of his success in solving the problem of adapting the electric light to domestic purposes has had the effect of bringing into public view a number of other contrivances for producing the same result. Among these, Werdermann's system appears to be perhaps the most promising; the following account of it we take from "Nature": "The principle of Werdermann's invention is that of keeping a small vertical pencil of carbon in contact with a large disk of the same material. In some earlier experiments he found that when he increased the sectional area of one carbon and reduced that of the other he produced an electrical light with the carbons in actual contact, a small arc appearing at the contact-point. The small carbon is a pencil three millimetres in diameter; the upper or negative carbon is a disk of two inches in diameter and an inch thick. The upper carbon is not consumed, so that the waste takes place only in the lower. In his lamp he places the disk uppermost with the pencil vertically beneath it, sliding up a metal tube which acts as a guide and contact. The pencil is kept in contact with the disk by means of chains attached to its lower extremity, passing over pulleys and down again to a counterweight of about one and a half pound. About three quarters of an inch of the lower carbon appears above the tube and is rendered incandescent by the passage of the current between it and the disk. This pencil is pointed, and retains its point all the time of burning. It is between this point and the disk that the small electric arc appears which gives the greater part of the light. In an exhibition of the system, ten lamps were shown in one circuit. The inventor believes that after further experiments he will be able to divide the current into fifty, one hundred, or even five hundred lights. Each lamp can be lighted and extinguished separately without affecting the others."

 

Dangers of Moldy Bread.—A singular case of poisoning from eating a pudding made in part of moldy bread is reported in the "Sanitary Record." The main facts of the case may be briefly stated as follows: The principal materials of the pudding consisted of scraps of bread left from making toast and sandwiches, and they had been about three weeks accumulating. To these scraps were added milk, eggs, sugar, currants, and nutmeg. The whole was baked in a very slow oven, and was subsequently eaten by the cook, the proprietor of the eating-house in which it was prepared, the children of the proprietor, and two other persons. All of these became violently ill, with symptoms of irritant poisoning. One of the children (aged three years) and one of the adults died. The necropsy of the body of the child caused the medical men to suspect poisoning, and accordingly the viscera, together with the remnant of the pudding, the materials used in making it, the matter vomited, etc., were sent to a chemical analyst, Mr. Alfred Allen, for examination. He made tests for several poisons, but without positive result. A puppy was fed with the pudding for two days without any poisonous effect. He was then led to look for ergot in the pudding, and was soon startled to find unquestionable evidence of its presence, as far as the chemical reactions went, though he was unable, with the aid of the microscope, to detect any actual ergot. From these facts Mr. Allen infers that the reactions hitherto supposed to be peculiar to ergot are common to other poisonous fungi.

 

Steering of Ocean-Steamers.—Among the reports of committees to the British Association at Dublin was one on the steering of screw-steamers. This report declares it to be an invariable rule that, during the interval in which a ship is stopping herself by reversal of her screw, the rudder produces none of its usual effects to turn the ship. In fact, under these circumstances, the effect of the rudder is to turn the ship in the opposite direction from that in which she would turn if the screw were driving her ahead. A ship with screw reversed requires, in order to turn a circle, double the radius of that required while steaming ahead; and, if it is difficult to govern her direction, it is more difficult to predict what that direction will be. When moving at full speed a screw-steamer requires five lengths more or less in which to stop herself, whereas by using her rudder and steaming on at full speed ahead she would be able to turn herself through a quadrant without having advanced five lengths in her original direction. Moral: When collision is imminent, steam ahead and be quick with the rudder. But, owing to the imperfection of the steering-apparatus now generally employed, quickness is impossible, and it takes a long time to put a large angle on the rudder. "The result is" (so say the Committee) "that it is often one or two minutes after the order is heard by the men at the wheel before there is any large angle on the rudder, and of course, under these circumstances, it is absurd to talk of making use of the turning qualities of a ship in case of emergency. The power available to turn the rudder should be proportional to the tonnage of the vessel, and there is no mechanical reason why the rudder of the largest vessel should not be brought hard over in less than fifteen seconds from the time the order is given. Had those in charge of steamships efficient control over their rudders, it is probable that much less would be heard of the reversing of the engines in cases of imminent danger." Clearly this is a question which calls imperatively for regulation by the Admiralty or some other competent authority.

 

The Candle-Fish.—The eulachon, or candle-fish (Thaleichthys pacificus), an inhabitant of the Pacific Ocean in the vicinity of British Columbia and northward, is worthy of a place among the curiosities of the animal kingdom. It is a small fish—about fourteen inches in length—and in appearance resembles a smelt. It is the fattest of all known fishes; and, in fact, the Indians use it, in the dried state, as a candle. On touching the tail to the fire it burns with a bright flame till the whole is consumed; more usually, however, a wick of woody fiber is passed through the body of the fish from end to end to insure continuous combustion. But the candle-fish is also employed as an article of food, and in spite of its fatness—indeed, on account of its fatness—is highly esteemed by the Indians as a warming food for winter. For this purpose they are dried and smoked in the spring, and then packed away. So preserved they are eaten whole, or the oil is tried out and eaten as butter. The take is usually very large, and only a small portion is dried and smoked. The remainder are piled in heaps till partial decomposition has set in; they are then packed in large boxes and the oil pressed out. This oil also is used as food, and it is said to be not altogether intolerable to the stomach of civilized man. The appearance of the first shoal of candle-fish in March is greeted by the Indians with extravagant demonstrations of joy. It is their Easter.

 

The Storage and Purification of Water.—In one of a series of papers on "Water-Supply for Small Towns," now publishing in "The Plumber and Sanitary Engineer," Mr. E. S. Philbrick has some remarks on the best material for constructing cisterns. He gives the preference to brick, as being sufficiently durable, and at the same time cheap. As brickwork is not adapted to resist tensile strains, brick cisterns, if of any considerable size, can not withstand water-pressure, by the strength of walls alone. So we put them underground, getting the earth-pressure from without to balance the water-pressure from within, and at the same time protect them from frost. The circular form generally used is strong enough in itself to resist the earth-pressure when the tank is empty, for this is a compressive force. The extended application of hydraulic cement thus enables us to construct, in almost any part of the world where commercial relations exist, an imperishable and incorruptible water-tank, so far as its own materials go.

But cistern-water will always be more or less contaminated by the accumulation of dust swept down from the roof. Hence a cistern should be thoroughly cleaned from time to time as occasion may require. Every cistern intended to hold water for drinking should have a filter. For this purpose a chamber can be parted off on one side the cistern, within which the suction-pipe takes the water for use, and the filtering material placed so as to pass the water through holes in this partition. Sometimes soft or half-burned bricks are used for this partition, through the pores of which the water passes freely, if sufficient surface be used. If, however, it be desired to remove any dissolved impurities from the water, these mechanical filters, whether brick, gravel, sand, or sponge, are useless, and recourse must be had to a charcoal or spongy iron filter, which acts chemically upon various substances in solution, burning them up, as it were, by the oxygen within the filter.

These filters, however, require such frequent cleansing for the renewal of their efficiency, that they can only be used effectively in a portable form, and cannot therefore be built into the tank.

 

Products of Coal-Gas Combustion.—From a lecture by Mr. Thomas Mills, before the British Association of Gas Managers, we take the following remarks on the products of combustion of coal-gas: "Of such gas, supposing its specific gravity to be ·5, or half that of air, a cubic foot contains about half its own weight of carbon; and, if this cubic foot of gas be burned, it will give a little more than half a cubic foot of carbonic acid, or, in weight, 488 grains. Again, a cubic foot of coal-gas, of ·5 specific gravity, contains about 41 grains of hydrogen, and this hydrogen in burning will produce 372 grains of water. If we regard the quantity of air necessary to supply the requisite quantity of oxygen to a cubic foot of gas, it lies between five and six feet of air. For every cubic foot of gas burned we require the oxygen of between five and six cubic feet of air, and this will give half a cubic foot of carbonic acid as a result. When we come to estimate the total products of gas-combustion in such a place as London, the figures are really startling. The quantity of gas consumed in London annually may be taken approximately at about 15,000,000 cubic feet. The amount of carbonic acid given off during a year by the combustion of these 15,000,000 of cubic feet is 433,000 tons. The amount of water produced by the combustion of this quantity of coal-gas is 360,000 tons, or 80,000,000 gallons. One of the largest, if not the largest gasholder-tanks in London, is at the Phoenix Works at Kennington. That gasholder-tank, supposing it had no internal cone, and were perfectly flat at the bottom, would hold 10,000,000 gallons of water, if filled to the brim. You might empty that tank and fill it eight times over in a year with the water produced by the burning of the coal-gas consumed in the metropolis during that time."

 

How the Penguin rears its Young.—In the southern part of the Indian Ocean—about latitude 40° south, longitude 80° east, or about half-way between Africa and Australia—are the two islands, St. Paul and Amsterdam, both of recent volcanic origin, and both the favorite resort of the albatross. But they are most of all remarkable for the number of penguins which have here their permanent residence. According to a writer in Chambers's Journal, these penguins form a rude sort of commonwealth among themselves. In the rearing of their young they exhibit considerable dependence on one another. The hens lay one or two eggs, never more, in a hollow of the ground or on a little grass. The task of incubation is performed by both parents, the one "off duty" going to the sea to procure food for itself, and when the young are hatched bringing a supply for the family. "Where tens of thousands of nests are collected together so closely that the visitor cannot walk without demolishing new-born nestlings or eggs at almost every step, it is difficult to understand how each bird knows its own nest, eggs, or nestling, as it appears to be the case until the young are able to walk about for themselves. Then the latter form into 'infant school,' presided over by several matrons, and ask and receive food from any charitable passer-by, and the social system, so far as it goes, has attained its highest point. There is no longer any recognition of meum and tuum, but a determination on the part of each adult to do the best for the rising generation, without regard to the petty rights of property so stoutly maintained and hotly contested in the egg stage. Woe betide the incautious or over-confident experimenter who shall remove one of these fierce motherly things from her nest with his hands!—the penalty will be a succession of stabs, which produce notoriously painful wounds. But the occupant of the nearest nest will always receive and tuck under her, together with her own brood, the young of a dispossessed neighbor. All through the nursery are well-beaten paths along which the birds hop in single file with most grotesque action to and from the sea; and from the nests on either side come sharp stabs at the legs of the intruder, a deafening roar accompanying his progress the while, and an odor assaulting his nose which only those who have sailed in a guano-ship can realize. The time has now arrived when the young must be taught their first swimming-lessons, and the rudiments of that aquatic life to which their special structure confines them. From the rookery to the sea they advance, hopping with both legs together, and jump feet foremost bolt upright from a ledge into the water. Then, and only then, are they thoroughly at home, and, making use of nothing but the powerful scaly flippers, dart about with the rapidity of a fish. Frequently the old bird will rise to the surface with a young one balanced on each flipper, maintained in its precarious position by the grasp of its own tiny paddles, and no doubt vastly enjoying this introduction to life and the novel experiences to be met with under water."

 

A Unique Surgical Operation.—A surgical operation of probably unique character is described in the Lancet, by Dr. Alexander Patterson—namely, the employment of a piece of dog's bone in the treatment of ununited fracture. The patient, while at sea, sustained a simple fracture of both bones of the left forearm. The arm was at once put in splints, and so remained for some weeks. On removing the splints it was found that the bones had not united. It was not till eight months after the occurrence of the accident that the man was admitted to the Western Infirmary of Glasgow. Repeated efforts were made to induce the broken bones to reunite, but all without avail; and finally it was decided to amputate the arm. In the absence of the regular surgeon, Dr. Patterson took charge of the case, and obtained permission to make an attempt at saving the limb. The operation is best described in the author's own words:

"The patient was taken and placed under the influence of chloroform, while at the same time a retriever dog was being anæsthetized. I made an incision along the ulnar side of the arm, cutting down upon the ends of the fractured bone, and removing the fibrous band which alone formed the bond of union; the rounded points were removed by the saw, and a hole drilled obliquely through each squared end. The same process was repeated on the radial side, when it was found that an interspace of about three-quarters of an inch existed between the two fragments of the radius. In the mean time, one of the senior students had exposed the humerus of the quadruped, completely denuded of every tissue except the periosteum. The length of bone was accurately measured (three-quarters of an inch), while from half an inch beyond the end of the necessary length the periosteal covering was rapidly but carefully dissected, the bone sawed through, a hole drilled in either end obliquely, as in the radius and ulna, and at once placed between the ends of the radius, where it fitted accurately. Wires having been passed through the holes, the bones were firmly tied together, the loose half-inch margin of the periosteum of the foreign bone being carefully spread over the periosteum of the radius. The wound was stitched with silver wire, the bone sutures coming out at each end of the incision. Wires were passed through the ulna, tied together, and the wound treated in a similar manner. The entire operation was conducted under the carbolic-acid spray. The arm was put up in gauze, and held in two rectangular splints."

We need not give details of the patient's condition from day to day. Suffice it to say that one wound remained open for twelve months, and that then the dog's bone, reduced to about half its size, came away, after which the wound healed completely. The radius seemed to have fallen in somewhat toward the ulna, leaving a slight deformity. The man is by occupation a marine engineer, and is now able to resume his ordinary pursuits. Dr. Patterson had hoped that the strange bone might find a new home for itself in the human arm. This failing, he was confident that it would secure perfect alignment and steadiness in the ulnar fragments. In the latter respect the event fully justified his anticipation. He still believes in the possibility of incorporating a foreign bone.

 

Ancient Hygiene.—It would be matter for a very interesting inquiry to ascertain how it happens that, with regard to many abstruse questions of practical science, hygiene for instance, the ancient Hebrews, Romans, Greeks, etc., reached results which for correctness put to shame the ignorance of later times. An illustration of this truth is given in a memoir by Dr. John Spear, lately published in the "Lancet." He first speaks of the precautions to be taken in selecting sites for human habitations. From the "Mishna" we learn how carefully all unclean things were removed from the vicinity of Jerusalem and the temple; and the investigations of Signer Perotti in the site of the ancient Jewish capital have shown how complete were the systems of sewers and the means of sewage precipitation and disposal. We find again that the Latin author Vitruvius, in his work "De Architectura," supposed to have been written in the reign of Augustus, in giving directions for securing healthy sites for towns, lays special stress on the necessity of a porous soil, and, in order to secure the ventilation of that soil, on perfect subsoil drainage. The views of Hippocrates on this subject, as also of Pliny and of other classic writers, might be studied at the present day with profit. Thus it would appear that the memorable researches of Pettenkofer, in a great measure, serve only to make us acquainted with the laws which were perfectly well known to the men of olden time. Then, as to practice: in the ancient cities of the world—Rome, Carthage, Herculaneum, Nineveh, and Alexandria, we know how well pollution of the soil was guarded against. What most judiciously executed works for this and other sanitary objects existed, recent discoveries have revealed. Probably in all these places too, and certainly in Rome, interment within the city walls was forbidden. "It is worthy of note," observes Dr. Spear, "that at this period of history pestilences and epidemics were not of common occurrence, and when they appeared they were usually clearly traceable to famine or to war. But to this enlightened and golden age succeeded one of darkness and intellectual torpor. Sanitary measures were forgotten or ignored; filth accumulated in crowded towns; the practice of intramural sepulture became general. The soil, the air, the water, we read, were impregnated with decomposing matters. As a result we have recorded those most destructive pestilences of the middle ages. The plague, the black-death, fever, and small-pox, swept over the land. . . . Pestilences were ascribed to the pleasure of Almighty God."

 

How to keep cool.—The experiences of an English visitor to the Paris World's Fair, as recorded in the "English Mechanic," convey a useful lesson on the means of enduring without serious discomfort the extreme of summer heat. This gentleman, Mr. D. Winstanley, writes that he went to Paris in March, the weather then being decidedly cold. As the temperature gradually increased he noticed that his ordinary clothing became uncomfortable whenever at 8 a. m. the thermometer indicated 70° Fahr. Accordingly, when that temperature was indicated, he made it a rule to adopt linen clothing, and he then enjoyed a comfortable temperature throughout the day. As summer advanced and the heat increased he never felt hot when clad in linen. Even when the thermometer had risen to 97° Fahr. in the shade, he felt no uncomfortable sensation of being hot, and, furnished with a "havelock," strolled leisurely in the blazing sun for hours, the thermometer indicating 125° Fahr., without discomfort, and without consciousness of perspiration. Mr. Winstanley adds, however, that during the hot weather he lived almost wholly on vegetables and fruits—peas, beans, melons, etc.—using no meat, and above all no fat. He takes occasion to commend the French style of windows in dwelling-houses. "Instead of our miserable idea of an horizontal section," he writes, "which permits at most only one-half of the window aperture to be opened for the admission of air, the French employ the vertical division, and open the windows inwardly on hinges as we open doors. The window apertures are also large, or rather high, descending to within eighteen inches of the floor, and ascending to within four inches of the ceiling. Outside these are latticed shutters. When the windows are open and the shutters closed the sun is effectually kept out, and the free circulation of the air is scarcely interfered with. A light balustrade of iron, within the shutters and without the glass, serves to prevent falling through the windows."

 

Destruction of American Forests.—It has been for some years apparent that the United States supply of timber must fail at no distant day, unless some concerted measures are taken for growing new forests or in some way preserving the old. The present condition of the lumbering business will be understood from the following facts, published by the St. Paul "Pioneer Press," and based on the observations of Mr. James Little, a lumber-merchant of Montreal, who has long studied this subject: Of the twenty-six States comprising the New England, Middle, Western, and Northwestern, to the Rocky Mountains, only four are now able to furnish lumber-supplies beyond their own requirements; the four being Maine, Michigan, Minnesota, and Wisconsin. But Maine is almost stripped of her pine-forests, and lumberers have to go to the head-waters of the rivers in search of spruce, while mere saplings, six or seven inches in diameter, go to the mill. In a few years Maine will have neither pine nor spruce for home consumption. The northern parts of Michigan, Wisconsin, and Minnesota, are the only localities of the whole twenty-six States which can furnish supplies of white pine beyond the home demand; but they will not be able to do so, Mr. Little affirms, for more than five or six years longer. The main streams are all stripped, and the dependence of the lumbermen is now on the head-waters of the tributaries. In 1870, according to the census report, there were in the United States 173,450 industrial establishments, employing 1,093,202 hands, devoted to the manufacture of wooden articles. The impression prevails that when our supply of lumber fails, as it must inevitably within the next ten years, we can find in Canada a supply that will not be exhausted in centuries. But this is an error; at least, Mr. Little asserts that there is not from Manitoba to the Gulf of St. Lawrence as much pine, spruce, hemlock, white-wood, and other commercial timber, as would supply the United States for even three years! In the light of such facts as these, it behooves the people of this country to seriously consider the subject of reforestation and the protection of young timber-trees.

 

Movement of Water in the Suez Canal.—The currents of the Suez Canal and the action of the prevalent winds on the water therein have been studied by M. Lemasson, who finds that Lake Timsah and the basin of the Bitter Lakes, the former in the middle of the line of navigation, the latter nearly at the middle of the southern branch of the canal, constitute two great regulators, at which the tidal currents from the two seas respectively expire. The north and south branches of the canal are not, however, independent as regards the movement of their waters. The dominant winds in this region blow, from May to October, from the north and northwest, and raise the mean level of the waters of the Mediterranean at Port Saïd, while they depress the mean level at Suez. The difference of level, which attains almost sixteen inches in September, sets up, in summer, a current from the Mediterranean to the Red Sea, which is interrupted by the tides, but nevertheless carries a considerable volume of water from north to south. In the winter, on the contrary, the south winds blow strongly, and the mean level of the Red Sea is then higher than that of the Mediterranean, the difference attaining a maximum of nearly one foot. The general direction of the current of the canal then sets from the Red Sea to the Mediterranean. The volume of water flowing annually from sea to sea is estimated at 400,000,000 cubic metres, and this with the tidal currents annihilates the effects of evaporation at the surface of the lakes, and aids the solution of the great salt deposit in the basin of the Bitter Lakes, which, instead of increasing, is diminishing, especially in the line of transit of ships.

The Parasites in Pork.Cysticercus cellulosæ, familiarly known as "measles" in pork, on passing into the human economy may develop into the common tapeworm. Analogous entozoa are sometimes found in beef, veal, mutton, and other meats, but the great source of these formidable parasites is pork. They can be easily detected in the carcass of a pig that is infested by them. "They are in the muscles," writes Dr. Vacher, in a paper read before an association of health officers, "between the fibers, between the muscles, on the surface of the muscles, and even in the walls of the heart. . . . Specimens from the same beast," he continues, "are nearly of the same size, but specimens taken from different beasts vary considerably in size. The egg-shaped investing bladder is scarcely ever less than an eighth of an inch in length, and it sometimes measures half an inch, so that it may be easily seen and removed. It is semitransparent, and contains a clear fluid, and what looks like a little white ball. On transferring the bladder to a glass slip, a touch with the point of a knife will suffice to rupture it, and if you then press a cover down upon it you have a preparation in which the rostellum and circlet of hooks may be distinctly seen with an ordinary lens." When meat is a little dry from exposure to air the cysts collapse, and are not distinctly visible. Dr. Thudieum recommends that such pork be submerged in water which the cysts will absorb by endosmosis.

 

Proposed Domestication of the African Elephant.—While the Asiatic elephant is in India domesticated and employed as a beast of burden, the African elephant, living, has no economic use, and is merely hunted for "sport," or for its tusks, hide, and flesh. It is now proposed to attempt the utilization of the African elephant as an aid in the exploration of the "Dark Continent" and for the transportation of goods from the coast to the fertile plateaus of the interior. Even in the Cape Colony, to say nothing of central Africa, elephants are numerous, and one troop has been observed within fifty miles of Port Elizabeth. Sir J. Fayrer suggests that on this troop the attempt at domestication might first be made. According to him, the African elephant is as well fitted for labor as the Asiatic, and could be as easily tamed and trained. That this is the case is amply proved by the state of docility to which the male and female African elephants in the London Zoölogical Garden have been reduced by their keeper. They are just as obedient, intelligent, and free from vice as their Asiatic congeners, and there appears to be no room for doubt that they might be utilized to just as good purpose. The importation of a few of the officers who have had experience in catching and training elephants in India, together with a few trained Indian elephants to commence the work, would very soon put the value of the project to the test.

 

Relation of Brain-bulk to Intelligence.—From observations made on numerous series of human crania, Dr. Lebon, of Paris, infers that intelligence is in proportion to the volume of the cranium. By comparing these series of crania, it is also found that the superior races present a much greater number of voluminous crania than the others. The same phenomenon is presented in proportion to the degree of civilization; the Parisian crania of the twelfth century present, for example, a less volume than the crania of modern Parisians; at the same time the difference between individuals becomes more considerable. Dr. Lebon does not believe that stature exercises any considerable influence on the volume of the cranium and the weight of the brain. Nevertheless, with equal height, the woman has a brain less heavy than the man. The author, from a study of seventeen male and seventeen female brains, found between them a difference of 172 grammes to the advantage of the former. It is worthy of remark that, among the superior races, the cranium of the women is generally much less than among the inferior races. This is due, Dr. Lebon says, to the insignificant part taken by woman in the work of modern society. There is a constant inequality of development between the two halves of the brain, which is sometimes more developed on the right, sometimes on the left, without race or state of intelligence appearing to have any manifest influence on the direction of this inequality of development.