Popular Science Monthly/Volume 27/May 1885/Popular Miscellany

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Popular Science Monthly Volume 27 May 1885  (1885) 
Popular Miscellany
 

POPULAR MISCELLANY.

Fifty Years of the Essex Institute.—Professor E. S. Morse has published a review of the condition of zoölogy fifty years ago and to-day, in connection with the growth of the Essex Institute, which has just completed its first half-century. The institute has always kept true to its name. It has been wholly for the benefit and in the interests of the county of Essex, in every corporate town of which but one public meetings have been held, to the number of two hundred in all; while the enthusiasm of its members has often led it beyond the limits of the county and of the State, into, in all, some sixty-eight "out-of-the-way places—little villages, cross-roads, and hamlets by the sea." To these places the society has induced the celebrated naturalists of the country to bring the results of their researches, and the latest and freshest fruits of science. Further evidence of its county character is found in the facts that its members are scattered over the county, and that it has aimed especially at forming a collection of the animals and plants of the county, and has such a collection, which is not excelled by any other of similar character. When the Institute was founded, there was not a single text-book of zöology in our schools; now, every high and classical school has its classes in zoölogy and botany, and every college its special professor. Then there was not a single popular periodical devoted to those sciences; now there are a number of illustrated weeklies and monthlies with a large circulation, the earliest of them, the "American Naturalist," having been founded under the auspices of the Institute; and even the newspapers keep pace with the progress of science, and publish special articles on scientific matters of interest. Then, the science of archaeology was not born; now it is "the most vigorous and aggressive of the sciences," and one of the Institute's men, Mr. Putnam, "is, for the first time, teaching the country the proper and only way of exploring the mysterious mounds of the West." The little society of a few men and a library of a hundred volumes has grown to be a powerful body of three hundred and forty members, with a library of thirty-eight thousand volumes. POPULAR MISCELLANY.

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��Why Wool felts. The cause of the felt- ing properties of wool is generally attrib- uted to serratures on the surface of the fibers, which are supposed, when driven into the closest possible contact, to hook into one another, and so to hold together by what might be called a " beggar's-lice grapple." The validity of this theory was called into question by two gentlemen of Hartford Captain George R. Case, a microscopist, and Mr. Joseph Dawson, a woolen manufacturer. These gentlemen, obtaining samples of wool of different grades, subjected them to vari- ous manipulations, and found: 1. That a single fiber of wool, when manipulated by itself in a lubricant of soap, has no fulling property, but rather a tendency to lengthen the fiber ; 2. That a number of fibers placed side by side, just as they grew on the sheep, and with simply tension enough to take out the kinks, when manipulated with a lubri- cant of soap, have no felting property, 3. That fibers similarly treated, but with the roots and tips alternating, have no fulling or felting property, and no power of adhe- sion ; but, 4. That a number of fibers placed side by side, with the tips all one way or with the roots and tips alternating, without any tension, have fulling properties ; and, 5. That fine-carded wool, taken from a sec- ond breaker, with the fibers thoroughly mixed, has great fulling properties when properly manipulated. A sample of negro's hair of suitable length, which was found by microscopical examination comparatively free from serratures but slightly spiral in structure, manipulated in the same manner as the wool had been, was formed into a " well-felted sample of cloth." These and other experiments satisfied the authors that the fulling properties of wool or any other fibers were in proportion to the number of waves, curls, or kinks, and their degree of fineness, and that the serratures, per se, have little to do with the matter, excepting pos- sibly that which may be due to friction. " To the question, What is the cause of the fulling or felting of wool ? the simplest an- swer possible is, it is the looping and in- terlooping, locking and interlocking of the fibers until they become inextricably en- tangled, but by interlooping and interlock- ing, and not upon the beggar's-lice prin- ciple."

��Spade-Foot Toads Dr. Charles C. Ab- bott contributes to the " American Natural- ist " a study of the hermit spade-foot toad {Scaphiophis Holbrooki), a rare animal, whose custom it seems to be to appear unexpect- edly in numbers, and, after a few days, sud- denly to disappear. Its name is derived from its long, horny index-toe, which may well be characterized as a spade, for it digs with it rapidly into the ground ; and its voice, immense for so small an animal, is like a steam-whistle. The spade-foots first visited Dr. Abbott's field of observation in May, 1874, 6tayed a few days, and were gone. Their next visit, ten years having passed without a single specimen being seen or heard, was April 10, 1884, in the same spot, a sink-hole in a dry upland field near Trenton, N. J. They remained till the 15th, when the weather became cooler and they vanished. Again they came, June 26th, after a rain-storm that flooded the sink-hole, and were found sitting on the grass-tufts and swimming in the pond by the hundred, all uttering their shrill, ear-piercing groans, through the day and night; but on the morning of the 28th all were gone. During this brief visit the frogs spawned, and the eggs were found attached to blades of grass and slender twigs. In about a week, those of them which were not destroyed by the retiring of the water were hatched out into tadpoles very much like other tadpoles. As they grew, about five per cent of the num- ber failed to develop as rapidly as the others. These " retarded " tadpoles were voracious cannibals, preying upon their fel- lows, now become " hoppers " and minia- tures of the adult spade-foots, so extensively that it was necessary to protect them to save any. In due time, the water was re- moved from the aquarium, and earth put in its place to about an inch in depth. " Upon this the young spade-foots were placed, and in less than one minute many had com- menced digging little burrows, into which they disappeared as the excavations deep- ened. ... In twenty minutes all but two of forty-four specimens were below the sur- face." A few individuals remained in the sink-holes as the water dried up into pud- dles ; but Dr. Abbott having neglected them, under the supposition that they would bur- row where they were, for ten days, could find

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��no trace of them upon an exhaustive search. He concludes that the animals must wander farther from their breeding-grounds than is supposed, or else must dig far deeper into the earth than to six or eight inches, as stated by Holbrook and De Kay.

Effect of Earthquakes on Buildings.

Mr. John Milne, of Tokio, Japan, has pub- lished some observations of the effects of earthquakes on buildings. In regard to the relative security of buildings on low and on high ground there is no universal rule, but each small area in an earthquake-region has its peculiarities. Theory indicates that soft, marshy ground is safer, because it will act as a buffer between the shock and the build- ing ; and the Temple of Diana, at Ephesus, was located with reference to this point. But experience at Tokio and Manila has shown repeatedly that there is very little, if anything, in it ; and hard, rocky strata, where the amplitude of motion is small, but the period quick as compared with the mo- tion in the inelastic material of the plains, proved the better foundation in Jamaica in 1692, and at Lisbon in 1755. Places to be avoided are the edges of cliffs, scarps, and cuttings. Europeans fasten the foundations of their buildings firmly in the ground, and their houses are much shaken. The Japa- nese put their structures loosely on top of stones or bowlders, and they escape seri- ous disturbance. Europeans and Americans build iron-bound houses to resist earth- quakes, and they resist them, though they get badly shaken, as a steel box would be ; but they are very expensive. The Japanese and the people of the west coast of South America build a kind of wicker - basket house a frame house with a light roof, which lives through the earthquake like "a reed shaken by the wind." The stability of such houses depends upon their not being firmly attached to the earth, and their nu- merous joints admit considerable yielding, so that the earthquake-wave passes through them before they begin to show its visible effects. A cheap aseismic house would be a low frame building supported by a num- ber of slightly concave surfaces resting on segments of stone or metal spheres in con- nection with the ground. Chimneys should be given a play-space around them, and not

��be in contact with the roof ; else, since the vibrational periods of the chimney and the roof never correspond, clashes will occur between them, and a shock and overthrow result. The pitch of the roof should not be great, or the tiles or slates will be shot off ; and the upper parts of all buildings should be as light as is consistent with strength.

Suggestions in School-keeping. Mrs. H. F. Wilson, in a paper read before the Educational Association of Alabama, tells how in her school she eschewed the system of marks and statistical reports as pernicious and false, and imposed as the one rule to govern the whole school, " Do right " ; and, as the real goal to be reached, excellence in everything. Incorrect sentences heard by any pupil are reported in a blunder-box, to be corrected by the school. Once a week, half an hour is devoted to the recitation of facts, drawn from the public press and other sources. Half of every holiday is given to microscopic, stereoscopic, or other instructive exhibitions. In connection with the teaching of music, information is col- lected concerning the old masters of music. Physical culture is attended to, and dancing is cultivated as an element of it. In this work the teacher finds infinite variety and enjoyment, and has been " filled with amaze- ment and enthusiasm at the immense amount of work pupils did unbidden, hunting over cyclopaedias and books of reference for in- formation when the text-book was obscure or inadequate."

Source of Atmospheric Electricity.

The source of atmospheric electricity has never yet been satisfactorily indicated, al- though various theories have been suggested to account for it. It has been attributed to aerial friction, to combustion or oxidation, to evaporation, and to condensation, to in- ductive or conductive effects of the earth's electricity, to convection currents, to electri- fied corpuscles coming from the sun, to solar radiation, to the friction of aqueous vapor against dry air, to capillary surface-tension of water, to the production of hail, etc. Professor Tait suggests that the mere con- tact of the particles of vapor with the air may suffice to produce the exceedingly small potential requisite to start the effects. He

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��has not had an opportunity to investigate his hypothesis, but he makes a few state. ments that illustrate how apparently small this potential may be. " To raise a single pound of water," he says, " in the form of vapor from the sea or from moist ground, requires an amount of work equal to that of a horse for about half an hour. This is given out again, in the form of heat, by the vapor when it condenses ; and the pound of water, falling as rain, would cover a square foot of ground to the depth of rather less than one fifth of an inch. Thus, a fifth of an inch of rain represents a horse-power for half an hour on every square foot ; or on a square mile, about a million horse-power for fourteen hours. A million horses would barely have standing-room on a square mile. Considerations like this show that we can account for the most violent hurricanes by the energy set free by the mere condensa- tion of vapor required for the concomitant rain. Now, the modern kinetic theory of gases shows that the particles of water- vapor are so small that there are somewhere about three hundred millions of millions of them in a single cubic inch of saturated steam at ordinary atmospheric pressure. This corresponds to l /ieoo or so of a cubic inch of water i. e., to about an average rain-drop. But if each of the vapor par- ticles had been by any cause electrified to one and the same potential, and all could be made to unite, the potential of the rain-drop formed from them would be fifty million million times greater. Thus it appears that if there be any cause which would give each particle of vapor an electric potential, even if that potential were far smaller than any that can be indicated by our most delicate electrometers, the aggregation of those par- ticles into rain-drops would easily explain the charge of the most formidable thunder- cloud."

How an Iron-Ore Bed was formed.

Professor James P. Kimball, of Lehigh University, has published in a single pam- phlet two papers on the iron-ores of the Juragua Hills, of the province of Santiago, Cuba, beds of a hematite or specular ore, which appears to be largely the result of the weathering of the highly basic rock which gives the geological character of the

��formation. These rocks, the eruptive ma- terial which gave origin to the iron-ore, consisted of proto-silicates, or silica com- bined with the protoxide bases, iron, lime, and magnesia, and with alumina. Under its new conditions at and near the surface, with access to oxygen in the atmosphere, circu- lating waters, etc., the protoxide of iron became rapidly further oxidized into ferric or sesquioxide, which is a comparatively stable product under conditions prevailing at the surface. The oxidation of the fer- rous to ferric oxide is attended with more or less complete dismemberment of the eruptive rock, little by little. Silica origi- nally combined with the ferrous oxide is isolated as silica. Silicates of lime, mag- nesia, and alumina form new aggregates among themselves. Soluble matter as fast as isolated enters into solution in circulat- ing waters, and is thus at hand to assist in the work of weathering. This work of alteration has gone on until a complete change has been wrought not only in the composition but also in the arrangement of the original eruptive rock. By the law of molecular attraction a process of concentra- tion has gone on simultaneously with the process of weathering decay. Homogene- ous material, such as ferric oxide, was col- lected by itself to a degree far greater than the other earthy residues, because, in the process of conversion from ferrous to ferric oxide, it has been in solution, and so in cir- culation, and has hence become finally de- posited under long - prevailing conditions of uniform circulation. The process here briefly followed out has gone on just below the surface, within the range of the circu- lating waters. The same action immediately at the surface is followed by waste or diffu- sion of the products of alteration. In the present case, the best of the ore-bodies are mainly, if not indeed wholly, replacements of coralline limestone.

Jnles Verne as a Scientific Authority.

The " Revue Scientifique " discusses a curi- ous question in giving its estimate of the value of Jules Verne as a scientific writer. It considers the judgment, which many of us are ready to give, that such science as is inserted into the framework of a romance is worse than no science at all, as too severe.

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��" Does any one believe seriously that a can- non-ball can be shot from the earth to the moon ? But what harm is there ill letting a child entertain a fancy of the kind for a few hours ? He amuses himself with it, and, while he is amused, he learns, without conscious effort, that the moon revolves around the earth, and the earth around the sun, aud that there are forces of gravitation and universal attraction, etc. . . . The false idea does no harm, for nothing is built upon it. ... I venture to say that it is advan- tageous to inspire children with the love of hazardous adventures, and the taste for the unknown that they find in all the romances of Jules Verne. They will encounter real difficulties soon enough to be discouraged from them earlier than they need to be. Not to see the difficulties is sometimes a good way to triumph over them. We have all grown timid and hesitating, and it is not a bad thing for us to be roused up to ardor in chimerical enterprises, in which the power of science is exhibited to us in the service of an energetic will. It is, perhaps, on this account, as much as for the amusement they give us, that we avow a strong liking for all of M. Verne's works. We might, if it were worth while, defend M. Verne on other considerations. When an idea enters the mind of a child, what matter is it how it gets there ? Whether it be in a romance, or in a lesson, or in a text-book, or in a familiar conversation, makes but little difference, so the result is acquired. To tell a fourteen- year-old boy that the diamond is crystallized carbon, and that fruitless efforts have been made to produce it artificially, is all very well, but will he remember it? Are these abstract facts interesting enough to stay? Possibly; but the contrary is probable. When you interest a child by relating to him the adventures of Cyprian, as he puts earth and charcoal into a crucible, and tries to crystallize it into a diamond, the scien- tific fact will not be forgotten ; and some day Cyprian will retire into the background, while the physical fact will be a permanent acquisition, which he will owe to this new mnemonic agency. It is more than mne- monics. While M. Verne entertains us with adventures, and fastens scientific facts upon us, he also gives us a taste for sci- ence. With him it is a goodly personage,

��smiling, affable, pleasant, greeting all who come."

Crickets and u Hair-Snakes." The so- called horse - hair snake, as is known to naturalists, is a parasite of the cricket, which only becomes active under water. Dr. H. C. McCook recently read a statement before the Academy of Natural Sciences of Philadelphia which indicates that the crick- ets are aware of the peculiarity of their para- sites, and take advantage of it to get rid of them. A lady having moved into a house which was a harbor for crickets, was troub- led by frequently finding the hair-snakes in her water-pails, a short time after the water had been brought into the house. She sat down to watch how they came there. In a short time she saw " a particularly pleth- oric cricket " mount upon the edge of the pail, and, after some uneasy movements, bring the tip of the abdomen just beneath the water, and, with a few violent throes, expel a black mass, which fell slowly through the water, and, before it reached the bot- tom, resolved itself into one of the worms. The cricket seemed much exhausted by the operation.

Toxic Effects of Smoking. Dr. Zulinski, of Warsaw, has made some experiments upon the effects of tobacco-smoke, which he determined to be a distinct poison, even in small doses. Its action on men is very slight when it is not inhaled in large quan- tities, but it soon becomes powerful in those who contract the habit of " swallowing the smoke." The toxical property is not due exclusively to the nicotine, but the smoke, even when disengaged from nicotine, con- tains a second toxical principle, called so- lanine, besides carbonic oxide and hydro- cyanic acid. The effects produced by smok- ing depend upon the nature of the tobacco and the way in which it is smoked. The cigar-smoker absorbs more poison than the cigarette-smoker, and he than the person who smokes a pipe ; while the one who uses a medium, by which the smoke is conducted through water, reduces the deleterious effects to a minimum. As a rule, the light-colored tobaccos are supposed to be the mildest, but they are sometimes artificially uncolored by chemicals, the presence of which is danger-

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��cms. Tobaccos are also generally adulter- ated, and, if the adulterating matter be woody, the smoke will be of high tempera- ture, and liable to cause inflammation of the tongue.

Antipathies^ Some strange cases of an- tipathy are recorded in the lives of eminent men. Erasmus was made feverish by the smell of fish. Ambroise Parr had a patient who would faint at the sight of an eel, and another who was convulsed on seeing a carp. Gardan was disgusted at the sight of eggs. A king of Poland and a secretary of France bled at the nose when offered ap- ples. A huntsman in Hanover, who would attack a wild-boar valiantly, ran away or fainted whenever roast pig was presented to his view. A person is told of who fainted whenever he saw a rose, and similar stories are told of antipathies to lilies and honey. Tycho Brahe abhorred foxes, Henry III. of France cats, mice, spiders, etc., and Mar- shal d'Albret pigs. There was " once upon a time " a lady who could not endure the sight of silk or satin. The man who would faint whenever he heard a servant sweep- ing is not so much of a stranger, and the one who was similarly affected by the sound of a bagpipe invites universal sympathy. Boyle was overcome at hearing the splash- ing of water.

Coinage Alloys. According to Professor W. Chandler Roberts, of the Royal Mint, the term alloy is usually applied in ordinary language to the mass formed by mixing a base metal with a precious one, while in sci- entific language it indicates the base metal which is added. Alloys are used in prefer- ence to pure precious metals for various reasons, chief among which is the fact that they are harder and more durable. The fact that their substitution for pure gold or silver may be a valuable source of revenue is a less commendable reason, but has not been without force. When a base metal is to be chosen for mixture with a precious one, it should be borne in mind that the re- sulting alloy must have the qualities of good color, ductility, and freedom from brittlc- ness. Silver forms a very ductile alloy with gold, but lowers the color, while copper forms a durable as well as a ductile alloy

��and heightens the color. A triple alloy of gold, silver, and copper may be made of delicate tints ; but it is difficult to assay and causes complications in the keeping of the accounts, and for those reasons the simple copper alloy is now almost universally used. At the mint, the qualities sought as most desirable in an alloy are: 1. Ductility; 2. Durability ; and, 3. Uniformity of composi- tion. The alloy is, besides, expected to be sonorous, or to impart the true " ring " to the coins struck from it, and to possess the degree of viscosity which will enable it to flow under pressure into all the fine lines of an engraved die, while at the same time the metal must be rigid enough to retain its impression when submitted to rough usage. A great variety of alloys have been used for coinage in the world's history, from pure precious metal down to base metal with only a trace of precious metal in it. Those now in use arc not very numerous. The fine- ness of alloys of silver is computed with reference to the troy pound. The compu- tation in the case of gold alloys is based on the singular " carat " system, the name of which is probably derived from the Kepdriov, a small Greek weight. This has within two years given way at the British Mint to a decimal system.

Making Champagne. The making of champagne is a process requiring extreme care and attention at every stage for at least two years. The grapes are picked with especial pains to keep any of them from falling or receiving bruises. Only the juice of the first pressing is made into high-class wine, and the quantity of this that shall be drawn is regulated by weight. Four hun- dred kilogrammes arc allowed for every forty gallons of wine, and when the desired quantity has been obtained the pressing is stopped. The protruding edges of the mass which have escaped the heavier pressure are cut off and subjected to a second pressure, the juice from which is called the first tallh. A thirdj pressure gives the second faille, and a fourth the redeche, juices that are considered fit only for the workmen. When the scum has risen in the wine-tubs it is taken off, and the casks are filled and fumigated with sulphur and put away, not quite full, in the cellar, for fermentation.

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��The wine is racked off into other casks when the fermentation has subsided, and becomes quite clear by the time the December frosts set in. It is then mixed, by bringing to- gether thirty or forty casks of the same growth, and blended. Tannin is added, to neutralize grease and deposits, and as much alcohol as is required. At a later stage a masque or deposit forms on the side of the bottle, the removal of which requires much care and skill and manipulation for several weeks. Afterward a sirup of sugar and alcohol is added, in proportions varying ac- cording to the country to which the wine is to be sent. Finally, the bottles arc corked, wired, and set on end.

Changes in the Color of the Hair.

Cases of changes in the color of hair other than to gray are not uncommon. Workers in cobalt-mines and indigo-works sometimes have their hair turned blue, and workers in copper green, by deposition of coloring-mat- ter upon it. This, however, is only a super- ficial coloring, and can be washed off. Pren- tiss records a case of a patient to whom muriate of pilocarpine was administered hypodermically whose hair was changed from light blonde to nearly jet-black, and his eyes from light blue to dark blue. These changes were due to increase of nor- mal pigment. Hauptmann relates a case of a body exhumed twenty years after burial, the hair on which had changed from dark brown to red. Leonard cites a case in which, after death, red hair was changed to gray within thirty hours. Other cases have been mentioned in which the color of the hair has been variously changed in conse- quence of disease.

Decline of Mnssnlman Indnstries. Ac- cording to a letter in the " Allgemeine Zei- tung," art and industry are in a lower stage in Algeria than in any other Mohammedan country, and their progressive decline is per- ceptible there from day to day. Persons may be seen walking in the streets of Al- giers, dressed in Moorish or Arabian cos- tumes, every piece of which is of European origin. Many branches of industry are ex- tinct, others are nearly so, and all show un- mistakable signs of decay. Many articles of European production are much cheaper

��than Mohammedan fabrics of the same kind, and are preferred for that reason ; and many which at the first glance seem to be Mo- hammedan are in fact European imitations. Most of the really Mohammedan articles which are found, such as carpets, cloths, and table-wares, are not Algerian, but of Moroc- can or Syrian manufacture. Arms are not made, for the wearing of them is forbidden by the French Government ; but the Kabyles make a kind of iron knife, which can hardly be called a weapon. The only native in- dustry still flourishing in the city of Algiers appears to be shoe-making, and this is be- cause the Algerine men refuse to wear Eu- ropean shoes ; but the women wear shoes of the prevailing fashion, with Louis XIV. heels. The cause of the depression of Mo- hammedan industry is the pressure of Euro- pean population and influence, which has been attended with a corresponding diminu- tion of the Turkish element.

Aryan Origins. Professor K. Penka, of Vienna, has recently published a work on " Aryan Origins," in which, according to Professor A. II. Sayce, an eminent linguist, he sets out with " the incontrovertible but hitherto neglected doctrine that language alone will not interpret for us the former history of our race. Without the aid of anthropology, it is not only useless, but misleading. The theories built on the as- sumption that language and race are inter- changeable terms, have introduced nothing but confusion into science, and have even left their scar on the politics of the day. It is only the skull in the hands of the anthro- pologist which can teach him the relation- ship of a people ; the language they speak, or may have spoken, will of itself tell him but little." Professor 0. Schrader has pub- lished, at Jena, a work regarding the Indo- Germanic race from the linguistic side, " in which," says Professor Sayce again, " for the first time a thoroughly critical method has been employed in determining the char- acter and condition of primitive Aryan so- ciety by means of the records of speech ; and the results are very different indeed from the idyllic picture of that civilized community to which Pietet and other writ- ers have accustomed us. The early Aryan comes before us as a coarse and uncivilized

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��nomad, unacquainted with the use of met- als, and protecting himself with the skins of wild beasts from the inclemencies of the climate." What his society was like, Pro- fessor Schrader thinks may be gathered from the remains left by the " pile-villagers " of the Swiss lakes, whom he regards as Ar- yans. Both Professor Penka and Profess- or Schrader express the belief that Europe, and not Asia, was the original home of the Aryan family. Penka considers the start- ing-point of Aryan emigration to have been Scandinavia, while Schrader suggests the northeastern lands of Europe generally as the most probable locality. The evidence, according to Professor Sayce, is now tend- ing to show that the districts in the neigh- borhood of the Baltic were those where the race or races who spoke the Aryan lan- guages originally dwelt, and that the Aryan invaders of Northwestern India were only a late and distant offshoot of the primitive stock who were speedily absorbed into the earlier population of the country as they advanced southward.

A Highway in the Himalayas. One of

the native explorers of the Himalayan re- gions of India lying beyond the British boundary, says Sir J. H. Lefroy, in his Brit- ish Association address, " describes a por- tion of his track at the back of Mount Everest as having been carried for a third of a mile along the face of a precipice at the height of fifteen hundred feet above the Bhotia-kosi River upon iron pegs let into the face of the rock, the path being formed by bars of iron and slabs of stone stretching from peg to peg, in no place more than eighteen inches and often not more than nine inches wide. Nevertheless, this path is constantly used by men carrying burdens."

Currency of the Cannibal Isiands. Mr.

Walter Coote has described some curious monevs of the New Hebrides and the Solo- mon Islands. On one of the islands he no- ticed a neatly-kept house, which he was told was the money-house. Entering it, he found a number of mats hanging from the roof, beneath which a fire was constantly kept up, under the effect of which they became covered with a black, glistening coating

��and adorned with festoons of soot. It was a man's business to keep the fire always burning, and so low as not to scorch the mats. A well-colored mat is worth about as much as a well-grown, vigorous boar. This is the strangest of all kinds of money, for it must never be taken from the money- house, even when the title in it is trans- ferred from one owner to another. The inhabitants of Santa Cruz Island use for money rope-ends, about an inch thick, and ornamented with scarlet feathers, which are worn about the waist. The traveler could not obtain new coins of this kind, but found them current everywhere. The specimens he bought were already old, and the feath- ers grown dingy. The money of the Solo- mon Islands consists of neatly-worked pieces of shell of about the size of our shirt-but- tons. They are strung on strings about four yards long, and are distinguished un- der the names of red and white money. Dog-teeth are of higher value, and compar- able to our gold coins. They are usually worn on a string around the neck. Mr. Coote saw a necklace of this kind that was valued at about a hundred dollars. Marble rings are also worn on the breast for orna- ments, and as valuable money. The cur- rency-table of these islands would be about as follows :

10 cocoanuts=l string of white-money.

10 strings of white-money = 1 string of red-money, or 1 dog-tooth.

10 strings of red-money = 1 isa, or 50 dolphins' teeth.

10 isa = 1 fine woman.

1 bahika, or marble ring = 1 head with the head-antlers, or 1 good hog, or 1 useful young man.

Theory of Lubricants. In a British As- sociation paper on the theory of lubricants, Professor Osborne Reynolds referred to some experiments by Mr. Tower, which showed that, when the rotating journal with its box was immersed in a bath of the lu- bricant, the resistance was not more than one tenth of its value in ordinary oiling, and that the journal was less likely to heat at higher than at lower speed ; and that if, after running the journal for some time in one direction, a reversal was made, great heating would result. This was to be ex-

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��THE POPULAR SCIENCE MONTHLY.

��pected, in the light of an observation made by Professor Reynolds, that there must re- sult a difference of pressure on the two sides of the vertical line through the center of gravity in the thin space between the box and the journal the maximum being on one side or the other, according as the rotation is one way or the other ; for, un- doubtedly, the box and journal became adapted to each other for a certain direc- tion of running, and when a reversal was made some time would elapse before a re- adaptation would be completed. This would explain why a new journal and box would always heat on first being run, however per- fect they might be.

Deaths by Poisoning. According to the English Registrar-General's reports, deaths by poisoning occur with alarming frequency in the ordinary course of events. In 1881, 569 deaths were recorded in England alone from this cause; in 1882, 599, or one in every 863 of the total deaths registered. Fully two fifths of the cases in the latter year were classified under the heading " ac- cident and negligence " ; the rest, 288, were suicides. Of the deaths through accident or negligence, 85 were occasioned by opium, laudanum, and morphia ; 18 by lead com- pounds ; 34 by the four stronger acids hydrochloric, nitric, sulphuric, and carbolic ; 14 by chloral ; 11 by phosphorus ; nine by arsenic ; six by chlorodyne ; four by chloro- form ; and four by soothing -sirup. How came the victims of these poisons to take them accidentally in fatal doses ? The medi- cal reports on the subject trace the mistakes to two principal causes the giving or tak- ing of overdoses of certain remedies con- taining poisons, and the substitution of one bottle or substance for another, as where bottles of all kinds of things are piled to- gether in the cupboard, and, in the nervous- ness of haste or in carelessness, the wrong one is taken. The remedies for these dan- gers ought to be obvious. One is, never to give an infant an opiate or other powerful soothing remedy without first obtaining the sanction of a doctor. Another is, that no patient taking powerful remedies should be permitted, or 6hould permit himself, to measure or repeat the dose himself. A third is, never to place bottles or packets

��containing poison alongside of or near any- thing that is to be taken internally. Fourth, never to put any poison into bottles, jugs, or cups which children or any other persons are apt to associate in their minds with sub- stances not in themselves dangerous. The last remedy is sovereign. It is, not to keep strong remedies on hand.

Relation of Color and Flavor in Fruits and Vegetables. Mr. Emmett S. Goff re- cords in the " American Naturalist " some investigations he has made to determine whether there may not be a law of relation between the color and flavor in fruits and vegetables. He was led to his experiments by the observation that in several fruits and vegetables, such as onions, currants, to- matoes, and raspberries, a white or light- colored flesh is accompanied by a milder and more delicate flavor than exists in other va- rieties of the same fruit or vegetable hav- ing a dark-colored flesh ; also that seme vegetables are " blanched " to give them a more delicate flavor. The usual aim in im- proving the qualities of fruits and vegeta- bles is to intensify the desirable qualities and eliminate the undesirable ones. It is evident, therefore, Mr. Goff says, that, if the color of the flesh has a direct relation to its flavor and tenderness, we have a valuable index in the work of selection. If by whit- ening the flesh of a fruit we can eliminate acid and solidity, or if by darkening the flesh of another fruit, already too tender and in- sipid, in the same way, we can heighten its characteristic flavor and increase its firm- ness, we have gained a new faculty in mak- ing the products of Nature subservient to our wants. Mr. Goff supports his view by the citation of a number of fruits and vege- tables of peculiar qualities, and quotes de- scriptions by various authors, which appear to be in agreement with it.

The Harp-Seal in the St. Lawrence River. It has been long known that the harp-seal (Phoca Qroerdandica) was accus- tomed to visit the Gulf of St. Lawrence for bringing forth its young ; but Dr. C. nart Merriam has collected evidence that its ex- istence in that river is far more general and fixed than had been supposed. Mr. Napo- leon A. Comeau, who lives near the point

�� � of the expansion of the river into the gulf, says that this species is the most abundant of all the seals of that locality, and roves up and down the St. Lawrence in its migra- tions iu immense numbers ; and he adds that it is tolerably common as far up as the Saguenay. From the information furnished by Mr. Comeau and from other data, it ap- pears to Dr. Merriam that the harp-seal is a permanent resident in the St. Lawrence ; that it spends the summer wandering about, some- times singly or in small schools, sometimes in larjre herds ; that it ascends the river at least as far as the Saguenay, and is common between Mille Vasches and Manicouagan ; that it frequents with considerable regular- ity particular shores and estuaries to feed on the small fish that congregate there at certain states of the tide ; that it works down the river early in the winter, and is particu- larly abundant about Point des Monts in December, January, and the early part of February ; that it then passes farther down to whelp on the heavy ice in the gulf ; that its young are born during the latter part of February or early March ; that, as soon as the young are able to shift for themselves, the parents at once return, passing Point des Monts in great numbers on their way up the river.

Alleged Nerve-exciting Properties of American Air. A correspondent of the Lon- don " Times " notices as a fact coming within his own personal experience the effect of the American air, particularly in New York, in exciting nervous sensibility. It is partly an effect of dryness, partly elec- trical, as is witnessed by the power some- times observed of lighting a gas-jet with the electric spark developed by shuffling rapidly over the carpet. It is observed also in the greater intensity of the effect of spir- ituous liquors in this country than in Eu- rope. ' It is partly local, for it is more marked in New York than in any ether place. It seems to be evolving a new type of mind, and ultimately possibly a new phys- ical type ; and the American appears to be becoming a more nervous and more spirited man. Hence, we have peculiarities in our statistics of insanity; our army of tramps " individuals of all classes, though mainly of the poorer, who can not endure the drive and strain necessary to keep up with their fellows, and whose inertia triumphs " and our cranks " people who carry eccentricity almost to iusanity, but are recognized as responsible persons." After noticing an increasing development of insanity among our native-born population, the writer men- tions two questions that suggest themselves : " Are we becoming a nation of madmen," or " are we developing a specialized race from those who can endure the pressure, and who by the survival of the fittest will form the future American stock, while the feeble in- tellectual natures will become tramps and lunatics ? "

The Weather and Health. -Dr. J. W.

Tripe read a paper at the Meteorological Con- ference, held in connection with the London Health Exhibition, on "The Relations of Meteorological Phenomena to Health." It is only recently that systematic observations have made the collation of knowledge on this subject possible. Ordinary variations of the barometer at ordinary elevations pro- duce but little effect on health. At consid- erable elevations disagreeable feelings fol- low the diminished pressure. Nevertheless, consumptive and other invalids have experi- enced relief at mountain-stations ; but this was because the reduced temperature, with the total change in the habits of life, more than compensated for the effects of the lessened pressure. In residences a sudden diminution of atmospheric pressure is likely to be attended with an escape of ground-air from the soil, and thereby to cause injury to health. Changes of temperature when rapid are liable to cause derangements in either direction ; otherwise man can with precautions endure a range of about 200 Fahr. without serious injury. Hot climates, however, eventually, unless habits are care- fully adjusted to them, sap the foundations of life among Europeans. The direct influ- ence of rain on man is not very marked in temperate regions, except by giving moist- ure to the air by evaporation from the ground and from vegetable life, and by al- tering the level of ground- water. Consider- able and sudden fluctuations in the level of the ground- water generally cause ill health, and if such water stands at less than five feet below the surface it is dangerous. Varying amounts of moisture in the air materi- ally affect health and comfort. Moist air is a better conductor of heat than dry air, hence we feel more chill in thaws than during crisp, cold weather. Fogs are in- jurious, net only on account of the vapors they contain, but because the air is satu- rated with moisture at a low temperature. Variations in temperature and pressure ex- ert a considerable influence on the circula- tion of air contained in the soil (ground-air), and this frequently contains that which it is not well to breathe. Winds affect health directly by promoting evaporation from the skin and abstracting heat from the body, and indirectly by their influence on the temperature and pressure of the air. Scarlet fever prevails most when the mean temperature is between 45 and 57 Fahr. Diseases of the lungs are fatal in proportion to the lowness of the temperature and the presence of excess of moisture and fog. Relations appear to exist between a high summer temperature and mortality from di- arrhoea. The relations between the weather and disease are not always uniform, for a discordance has been observed in the curves for whooping-cough, typhoid fever, and scar- let fever, between London and New York, and in diarrhoea between London and India. Better information is needed on this sub- ject.

Speetro-pbotomotric Study of Pigments.

Edward L. Nichols, Ph. D., in a paper read at the last meeting of the American Association on " A Spectro - photometric Study of Pigments," finds that the spectro- scope shows that pigments can not be con- sidered even in the roughest approximation as reflecting monochromatic licrht, but that they are more nearly related to white. Hence, " the attempt to express the hue of non-luminous bodies by comparison with isolated spectral tints is founded upon a false conception of the nature of the light which they reflect. To determine the hue of a pigment from the analysis of the light it reflects is a problem in physiological op- tics, the solution of which varies with the character of the observer's eye. The three primary color-curves of the eye must be determined, and the total intensity of each wave-length of the spectrum of the pigment

��must be divided in the proportions indicated by the color-curves into three components red, green, and violet. Summing up each of these components for the entire spec- trum, we obtain an expression for the hue in terms of the three color-sensations of which it is the resultant. In default of this method, which is difficult of execution, the curves themselves are an expression of the hue, the only requisite for the interpre- tation of which is practice in associating the sensation of color produced by pigments with the form of curve representing them."

The Manufacture and Applications of

Iridiin 1. The manufacture of articles from iridium has recently assumed considerable importance through the discovery of practi- cable methods for making the metal. Irid- ium is obtained, in Russia and California, as a by-product in the working of the ores of platinum and gold, and is found only in the condition of grains, not larger than grains of rice, or of a fine powder, and oft- en alloyed with platinum or osmium. It is one of the hardest substances known, being in that respect nearly the peer of the ruby, is not readily or permanently acted upon by oxygen, and is soluble in no single acid, and only slightly soluble in aqua rcgia. Its principal use hitherto has been for the point- ing of gold pens, for which purpose the grains had to be taken as they were found, and soldered on without working over. The discovery of the process for working iridium is due to two gentlemen of Cincinnati, Mr. John Holland, a gold-pen manufacturer, who found that it could be melted with phosphorus ; and Mr. W. L. Dudley, who devised a method for afterward eliminat- ing the phosphorus. Mr. Holland, seeking larger pieces of iridium than could be found in Nature, discovered, after many experiments, that by heating it to a white heat and adding phosphorus, with a few minutes more of heating, he could obtain a perfect fusion, and could pour out the molten metal and get a casting of it. The product proved nearly as hard as the nat- ural grains of iridium, and to have nearly all the properties of the metal itself, but, con- taining from 7"52 to 7*74 per cent of phos- phorus, was liable to fusion, and could not therefore be used for purposes, as in electrical apparatus, where it would have to withstand a white heat. Mr. Dudley undertook the removal of the phosphorus, and found that this could be effected perfectly by heating the metal with lime in an electric furnace. The manufactured metal will then resist as much heat without fusion as the native metal. Iridium is sawed by a copper disk between four inches and eight inches in diameter, making twenty-five hundred revolutions a minute, and dipping into a bath of cotton-seed oil and corundum or diamond-dust. Many new uses are opening for it since it has been possible to melt and cast it. It is used for draw-plates, to replace the ruby plate, in the manufacture of gold and silver wire; for knife-edges for scales and balances; for tipping hypodermic needles; for the negative poles of arc-lamps; and for many other purposes. One of the most important applications is for the contact-points of telegraphic instruments. These points outlive many platinum contacts, and do not oxidize or stick. Mr. Dudley is making experiments, with a fair promise of reaching commercial success, in the electric deposition of iridium.


The Chaldean Lunar Cycle.—M. Oppert recently read a paper before the Academy of Inscriptions and Belles-Lettres on an Assyrian inscription concerning lunar cycles. More than twenty years ago he discovered in the inscriptions of King Sargon allusions to a great lunar cycle one of the revolutions of which terminated in the year b. c. 712. He was afterward convinced that this cycle was the period of 1805 years, after which the series of lunar eclipses recur in the same order. The knowledge of this period supposes continuous astronomical observations among the Chaldeans already of many centuries' duration. They began the calculation of the period from the year 11,542 before our era. This is also the year in which the Sothiac periods (of the Egyptians) of 1460 years begin, one of which ended b. c. 139. These two cycles of 1460 years and 1805 years play an important part in the chronological computations of the ancient East. Twelve of each of them form respectively 17,520 and 21,660 years, or 292 and 561 sixties of years, numbers which occur in the Bible, according, to M. Oppert, to express the length of time between the Flood and the birth of Abraham, and from the birth of Abraham to the end of the history in Genesis.