Popular Science Monthly/Volume 17/June 1880/Popular Miscellany

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Popular Science Monthly Volume 17 June 1880  (1880) 
Popular Miscellany


Climate and Complexion.Correction.Messrs. Editors: I notice that in my article on "Climate and Complexion," published in your May number, I have, either in so many words or inferentially, made the statements that a dark pigment reflects the rays of light and heat better, and that it is a greater obstacle to their transmission than a light one. These, of course, as they stand, are quite wrong. What I should have said is, that a cuticle containing a dark pigment is less permeable by heat and light, because it is thicker and more opaque. For some reason, which I do not undertake to explain, the coloring matter of the skin, when abundant, is darker than when scanty. Hence, a cuticle containing a dark pigment is less transparent. And because abundance and consequent blackness of the pigment imply thickness of the cuticle, a dark cuticle does not transmit heat so readily as a light one.

J. M. Buchan. 
 Barrie, Ontario, Canada, May 3, 1880.

Summer Schools of Natural History.—We received, too late for insertion in our May number, the announcement of this summer's session of the Chesapeake Zoölogical Laboratory, which was to open April 22d at Beaufort, North Carolina, and continue until the 1st of September, under the direction of W. K. Brooks, Assistant Professor of Zoölogy and Comparative Anatomy in Johns Hopkins University. The house to be used as a laboratory is near the water, and the equipment includes boats, nets, dredges, aquaria, books, microscopes, and all the necessary appliances for collecting and studying marine animals and plants, and a steam-launch for dredging and surface collecting.

The fifth session of the Summer School of Biology at Salem, Massachusetts, will be held at the museum of the Peabody Academy of Science, Salem, under the direction of Professor Edward S. Morse. Professor George L. Goodale has kindly consented to give six lectures on physiological botany. The other instructors are Mr. John Robinson, cryptogamic botany; Mr. John H. Sears, analytical botany; Professor H. II. Straight, anatomy and physiology of the vertebrates; Mr. Charles Sedgwick Minot, embryology; Mr. Charles Fish, entomology. Mr. Morse will lecture on the invertebrates. The school will commence July 6th, and continue six weeks. It is designed expressly for teachers.

A Summer School of Biology will be opened at Drury College, Springfield, Missouri, on July 1st, to continue not less than six weeks. The course is designed mainly for teachers; and lectures, laboratory study, and excursions will be the chief means employed for carrying on the work. Mr. E. M. Shepherd, of Drury College, will instruct in the departments of Invertebrate Zoölogy and Cryptogamic Botany; Mr. C. H. Ford, of the State Normal School, is to have charge of Vertebrate Zoölogy and Phamogamic Botany; Mrs. H. C. Milner will give instruction in methods of teaching Elementary Science; and Dr. T. U. Flanner will instruct in Microscopy.


Rearing Silkworms in England.— Mr. Alfred Wailly contributes to the "Journal of the Society of Arts" some valuable notes on silk-producing bombyces which were bred in England during 1878. The Attacus Yama Mai, or Japanese oak silkworm, is difficult to rear, since it is in the egg state in the winter. The eggs have to be kept protected from the rain and the rays of the sun, and a special provision of young oak-trees which have been potted and protected from the frost, not forced, is recommended in case they hatch out too soon. The Attacus Pernyi, or Chinese oak silkworm, is very easy to rear in the open air, and will feed, like Yama Mai, on all species of oak. The young worms of the first brood hatch in June or the beginning of July, when there is an abundance of foliage to feed them. The species is reproduced with great facility. The hatching of the second brood in the fall should be prevented by keeping the cocoons in a cool place. Attacus cynthia, or the ailantus-worm, will feed, but not as well as on the ailantus, on the laburnum, lilac, and cherry. Attacus Atlas feeds on the apple, plum, peach, barberry, etc., and seems to have been reared with success. Attacus Sclene, a "magnificent species" from India, was introduced into Europe in 1878. The raising of it is apparently hazardous, for, though there were plenty of ova, and they batched out well, many of the larvae died in the last stage. A good account is given of the Attacus polyphernus and Attacus cecropia, from North America, which thrive well on a variety of plants.


About Beer.—An account of the production and consumption of beer throughout the world is given in the work of Mr. Von der Planitz on "Beer," which we have already noticed. The scientific investigations which have been made on subjects relating to fermentation have led to improvements in the processes of manufacture, and to the establishment of numerous schools or departments of schools in Germany and other countries where these subjects are specially studied. The foundation of a brewers' school in the United States has been talked of since 1871, and was one of the subjects considered at the Brewers' Congress held during the Great Exhibition at Philadelphia in 1876; but it has not yet taken shape. A considerable library of books relating to the practice and science of brewing has been published, and journals devoted to the business and the art are printed in Germany, Austria, Bohemia, France, England, and the United States. A number of scientific and experimental stations and laboratories have been established in Germany, where special researches are still carried on. A consolidation of works for brewing seems to be going on in all countries, so that the steady increase in the production of beer is attended by a decrease in the number of breweries. This feature is, however, common to most contemporary industries. Great Britain leads all other countries in the manufacture of beer, as well as in the production of barley, but returns a smaller production of hops than Germany. Germany is not far behind it, while the United States stands third in the list, and is followed by Austria, Belgium, and France. Belgium produces the largest quantity (149 quarts) per head of the population, and Great Britain (143 quarts) next. Germany (94 quarts) holds the third place by this criterion, and the United States (38 quarts) the sixth, being surpassed by Denmark and the Netherlands. The statistics of single states in Germany and of the Austrian Empire indicate that the amount of beer produced in those countries has about tripled within the last forty years. The production of Great Britain increased from 7,670,100 barrels in 1830 to 25,336,811 barrels in 1870. It consists chiefly of the ancient amber-colored ale and the modern dark-brown porter. The Belgian beers are the mars, a thin beer; the lambic, a strong and light-colored drink; and the faro, which the retailer himself prepares by mixing the other two kinds. The production of France has more than doubled since 1842. A strong lager-beer and a weaker small-beer are most in favor, and the foreign beers are in common use. The principal consumption is in the north, the people of southern France inclining more to wines. The same is the case in Italy, where a light, highly-fermented beer is produced, and a considerable quantity is imported from Austria; but no beer is used south of Naples. The manufacture and consumption of beer are increasing very rapidly in Russia, and a great deal is imported into that country from Austria and England. In Sweden and Norway nearly every man brews his own beer at home. No lager-beer was made in the United States forty years ago. In 1876 the President of the Brewers' and Maltsters' Association asserted that it was the great national drink which was to drive out whisky, and that there were 2,783 breweries, employing 35,400 hands, and producing 330,600,000 gallons. In all Europe and America 63,631 breweries produce yearly more than 3,480,000,000 gallons of beer.


Dampness and Diphtheria.— The opinion that a close connection exists between diphtheria and dampness of site is confirmed in some English reports recorded by Dr. Woodforde. In an outbreak of diphtheria at Purley in 1878, the cottage in which the earliest cases occurred was much shut in by trees, and, although it was very clean, it was damp and insufficiently ventilated, especially in the sleepiog-room3, it was exposed to the emanations of the cess-pit, and the water was not pure. At Ramsbury, where diphtheria was unusually fatal in 1877 and 1878, the ordinary sanitary defects were not much worse than in other villages, but the sites of many of the cottages were almost level with the river, and damp, with the subsoil water very near the surface. At Clifton-Hampden, where diphtheria had occurred for several years in succession, the ordinary defects of porous cess-pits and polluted water were noted, though not to so great an extent as at other places where there had been no diphtheria, but the village also appeared damp, and a stagnation of air was evidently occasioned by the number of trees adjoining the cottages. Sanitary improvements were instituted, the trees were thinned out, and a gale took away some that had been left, and the disease has not appeared in the place since.


Features of the Central Arabian Desert.—Mr. W. S. Blunt read a paper, last December, before the Royal Geographical Society, on a journey he had undertaken during the preceding winter from Damascus to the Jebel-Shammar, in the region of Nejo in Central Arabia, in which he passed through a country that no European had visited since the journeys of Mr. Palgrave and Colonel Pelley in 1863 and 1864. On his way he traversed the red, sandy desert of the Nefud. Here he observed a strange phenomenon, which he describes as the only feature of the tract. The whole surface of the plain is pitted with deep horseshoe hollows, called by the Arabs fulj, which are shown to be permanent in site and conformation by the shrubs and bushes which line their sides, and by the tracks which cross and recross each other in such of them as are frequented by sheep. They are absolutely uniform in shape, differing only in size, and are all set with great regularity toward the same point of the compass. In form they exactly reproduce the print of an unshod horse's hoof, the toe pointing westward and being marked by a steep declivity, while the bottom of the hollow slopes gradually upward to the heel, until it reaches the general level of the plain. The frog of the hoof is roughly represented by a number of shallow watercourses converging to the lowest point, the toe. Solid ground sometimes occurs at the bottom of the deepest of the pits. They vary in depth from twenty to two hundred and twenty feet, and in width from fifty yards to half a mile; the appearance of depth is often enhanced by a sand-mound at the western edge of the hole. As seen from the tops of the higher rocks, the fuljes "run in long, sinuous strings with a main direction generally corresponding with their aspect," which gives them still more the appearance of huge horse-tracks. This desert is provided with a vegetation of its own, and is well clothed in the hollows and most of the plain with shrubs. The plants include three grasses and "two considerable shrubs, almost worthy to be ranked as trees." The ghatha, growing sometimes to the height of twelve or fifteen feet, gives a bright, smokeless flame, and makes the purest charcoal in the world. The Bedouin tribes make their summer home here, living on the milk of their camels, and independent of water, and always finding pasture. Among the wild animals are the ostrich, hares, the ibex, the leopard, a marmot, snakes, lizards, hawks, buzzards, the bustard, and one or two smaller birds. A wild cow, or white antelope, related to the African antelopes, is native to the region. Tracks of this animal were seen at least a hundred miles from any place where it could have procured water, confirming the assertion that it never drinks. Of insects, the dragon-fly, beetles, ants, and the common house-fly were noticed. A specimen of the painted lady butterfly, famous for its long flights, was seen sunning itself on the rocks of Aalem. This insect could not have been bred at any nearer point than the hills of Syria, four hundred miles off.


Insect-Powders as Remedies for Flies and the Aphis.—The insect-powders commonly sold are the powdered flowers of different species of Pyrethrum. Of the two principal kinds, which are known as the Persian and the Dalmatian powders, the Dalmatian is the more energetic. The flowers, whether whole or powdered, preserve their activity for a long period. Samples, which have been kept for six months, show no depreciation. They may be used with much effect against house-flies simply by charging the room with the dust. Mr. William Saunders says, in the "Canadian Entomologist," that he has frequently, after having charged the air in his kitchen and dining-room at night, found all the flies lying dead on the floor in the morning. Few will escape when the room is closed for half an hour after using the powder. Mr. Saunders has also applied the powder with excellent success to the destruction of the green aphis in his greenhouses. The pests will fall to the ground when the dust is blown among the plants, and in the course of an hour or two the greater part of them will be found disabled; they seem, however, to be only stupefied, not killed, as the flies are, and must be taken care of. The powder gives a more convenient and pleasant remedy than any other that we have. It is, moreover, safe.


The Damposcope.—Professor Forbes has invented an instrument for detecting firedamp and determining the quantity of light carburetted hydrogen in the air, which he calls the "damposcope." Its construction is very simple. Over the mouth of a straight brass tube is fixed a tuning-fork; inside the brass tube slides another tube of the same metal, which is moved by a regulating screw, so that the compound tube can be lengthened or shortened at will, and this movement is registered on a dial. To ascertain the amount of fire-damp in the pit, the instrument is taken to the suspected spot, the tuning-fork is set vibrating, and the screw is turned until the maximum sound is emitted. The index is then read off. It appears that the quantity of gas can be determined to within one half per cent.


A New Metallic Compound.—Mr. Granville Cole, Ph. D., recently described before the British Society of Arts a new metallic compound which possesses some remarkable and valuable qualities. Its preparation is based on the principle that the sulphides of metals combined with molten sulphur form a liquid, which, on cooling, becomes a solid homogeneous mass, possessing great tenacity, and having a peculiar dark gray—almost black—color. Nearly all the metallic sulphides will form, with an excess of sulphur, combinations which have the same properties. The combination used by Dr. Cole in illustrating his address was formed of an ore of iron pyrites containing lead and zinc sulphides. It belongs to the class of compounds known as thiates, or sulphur sulphides. The compound has the advantages of a low melting-point, 320º Fahr., of expanding on cooling, of resisting atmospheric and climatic influences better than marble or bronze, of superior resistance to acids, alkalies, and water, and of being susceptible of a high polish. A polished surface of the metal has been exposed for six months in all weathers without showing any change, and another specimen suffered but little from a month's soaking in aqua regia. By reason of its low melting point it is easily prepared for the mold, and in consequence of its power of expanding it gives a nearly perfect cast. In the gelatine mold it yields an impression before the form of the mold is destroyed, and then, if the gelatine be allowed to remain on the metal till it is cooled, it remodels itself so as to be ready for the next casting. The compound, which is called Spence's metal, after its discoverer, Mr. J. Berger Spence, is useful for castings of all kinds, is better adapted than lead for the joinings of gas-and water-works, is suitable for vessels in which chemical processes not requiring a high temperature are to be conducted, and may be employed for joining railings to stones, for coating the holds of ships, for forming damp-proof shields in the walls of houses, for hermetically sealing bottler, for covering cloths, for preserving fruit and other articles of consumption, and to take the place of metal-lined boxes. For all these, and many other purposes, its cheapness and its general adaptability give it a great advantage, for its cost is calculated as only about one fourth that of lead.


The Electric Light and Vegetation.—Dr. C. W. Siemens has recently conducted experiments for two months on the influence of the electric light on vegetation. He planted the quick-growing seeds of certain common hardy vegetables in pots, and divided these pots into four groups, of which one was kept in the dark, one was exposed to the influence of the electric light only, one to the influence of daylight, and one to the influence of the electric light and daylight in succession. The electric light was applied for six hours each evening, and the plants were left in darkness during the remainder of the night. The plants that were kept entirely in the dark soon died; those exposed to the electric light only, or to daylight only, throve about equally; and those exposed to both daylight and electric light throve better than either. The experiments showed that the electric light is efficacious in producing ehlorophyl in the leaves of plants, and in promoting growth. It also appears from them that an electric light equal to fourteen hundred candles, placed at a distance of a little more than two yards from growing plants, is equal in effect to the average daylight of the English March. Other conclusions, which Dr. Siemens thinks he is justified in drawing from his experiments, are—that plants do not require a daily period of rest, but make increased and vigorous progress if subjected during daytime to sunlight and during the night to the electric light; that the radiation of heat from powerful electric arcs can be made available to counteract the effects of night frost, and is likely to promote the setting and ripening of fruit in the open air; and that, while under the influence of electric light, plants can sustain increased stoveheat without collapsing. The expense of electro-culture, being dependent on the cost of mechanical energy, may be made very moderate where natural sources of such energy, such as waterfalls, are available. The buds of tulips, placed in the full glow of an electric lamp during the lecture in which Dr. Siemens related his experiments, expanded into full bloom in forty minutes. It is said that in India, where the bamboo throws up its shoots at the beginning of the rains, it rarely does so with vigor before the occurrence of a thunderstorm, and that its growth is more rapid as the thunderstorms are heavier.


A Test for Watches.—The corporation of Yale College have established an horological bureau in connection with the Winchester Observatory, for the purpose of encouraging improvement in watchmaking and pursuing researches in whatever may aid in the construction of refined apparatus for the measurement of time. In connection with this object they have provided apartments and made other arrangements for testing the running qualities, as to regularity, etc., of such timepieces as may be submitted for the purpose. Certificates of performance are given to the watches thus tested according to the standard of excellence they show. The apartments include a room of the ordinary temperature (65º to 75º), a cold room (40º), and a hot room (90º), and the watches are tested in the vertical and horizontal positions. Eight classes of certificates are given, corresponding with different combinations of the several tests and their relative duration. In cases where no certificate can be given the movement will be returned to the maker, with a statement of its performance.


Snakes and Snake-Poison.—Professor Huxley, in a lecture on "Snakes," at the London Institution last December, said that no creatures seemed more easily destroyed by man and few less able to defend themselves; yet there were not many animals gifted with so many faculties. The snake can stand up erect, climb as well as any ape, swim like a fish, dart forward, and do all but fly in seizing its prey. The destructiveness of snakes to man is illustrated by the fact that twenty thousand human lives are yearly lost in India by their poison, and it might safely be said that they are a more deadly enemy to our race than any other animals. The speaker pointed out some very curious arrangements in the anatomical mechanism and jawbones, illustrative of the statement that the snake can not properly be said to swallow his prey; he holds on to it rather, gradually working it down its throat in a most leisurely manner, but never letting it go. He requires a very fully developed and effective apparatus of salivary glands for this purpose. The poison-bag of the venomous snakes is nothing but a modification of the salivary glands of the harmless species, the structure of both kinds being in almost all respects not only parallel throughout, but almost identical. As another instance of the close relationship, it was shown that the sharp channel-needle which conveys the poison of the cobra and its congeners is nothing but the development of the tooth which these murderous reptiles possess in common with innocuous snakes. The fact that the salivary gland was the poison laboratory of the deadly snakes, as well as the known properties of the saliva of dogs or other living creatures affected with rabies, appeared to Professor Huxley to point out the direction in which lies the solution of the difficult problem of the cause of snake-poisoning, and of a possible antidote against it. At present there was no man living who could heal the bite of the cobra, except by cauterization in very fresh cases. A fitting supplement to Professor Huxley's remarks is afforded by facts given in the reports of the Snake-Poison Commission of Calcutta, showing the number of snakes killed, and of deaths by snakes and wild animals in India. In 18*75, 270,185, in 1876, 212,371 snakes were killed in all India. The deaths by snakes and wild animals were 21,000 in 1875, 15,946 in 1876. These figures do not give the whole numbers, for the registries are incomplete in the English districts, and no registries are kept in the native states, so that it may be found hereafter that many thousand deaths must be added to complete the catalogue of annual disaster from snakes. The excess of numbers in 1875 is accounted for by the fact that the floods of that year drove the snakes to the high-roads and exposed places. Remedies are said to be known for the poison of all the snakes except the cobra.


Development of the Limbs of Saurians.—Professor O. C. Marsh has noticed some peculiarities in the limbs of the sauranodon, the new saurian described by him in January, 1879, which give it a special interest. Both the anterior and posterior limbs are less specialized than in any other known vertebrate above the fishes. In the fore paddle, the humerus alone is differentiated. Below this, the bones of the forearm, the carpals, metacarpals, and phalanges are essentially rounded, free disks, implanted in the primitive cartilage. The structure of the posterior limb is substantially the same. The most striking features of the limbs are the presence of three bones next below the humerus and the femur and articulating with them, corresponding apparently with the radius, intermedium, and ulna in the fore-limb, and with the tibia, intermedium, and fibula in the hinder limb, and the fact of six digits. These characters are held to mark a stage of development below that seen in any other air-breathing vertebrate, and only approached by the limb of the icthyosaurus. The intermedium seems, in the process of differentiation, to have been crowded out of its original position between the marginal bones of the second or epipodial series into the third or mesopodial series. In icthyosaurus, the intermedium is not entirely excluded from the third row; in plesiosaurus and all other reptiles the process is essentially completed. In some amphibians, the bone still separates the lower end of the two specialized bones above it. Sauranodon marks an earlier and most interesting stage in the differentiation, and indicates how the transition was accomplished. Some of the amphibians retain remnants of a sixth digit, and icthyosaurus often presents traces that represent lost digits; but with these exceptions the normal number of five digits is not exceeded in any other air-breathing reptile than sauranodon.


PSM V17 D297 Electric spark piercing glass.png


To pierce Glass with the Electric Spark.—In the usual process of piercing glass with the electric spark when the glass is thick, one of the wires has to be inserted in a bed of insulating resin, quite thick, and which has itself to be melted upon the plate of glass. The operation, involving the use of heat, is inconveniently long; and, besides, the trouble of cleaning the glass of the resin has to be gone through after the hole is made. The process described below by M. Fages, architect of the city of Narbonne, is easy of application, and requires only a few minutes for preparation and execution. The apparatus is so simple that any one can construct it for himself, and it may be used for an indefinite number of operations. The cut represents it in vertical section. It consists of 1.—A rectangular plate, A, of hardened, black India-rubber, which should be, for a coil giving a spark of four inches, not less than six inches long and four inches wide; 2. A brass wire, B, the bent point of which, C, screwed or pushed into the India-rubber plate, rises even with its top. To use the apparatus, we lay it horizontally on a table, and put the brass thread B in connection with one of the poles of the magnetic coil; then pour some drops of olive or other oil on the India-rubber plate above the point C, and put upon it the plate of glass D, which is to be pierced, taking care that no bubbles of air are inclosed. The oil causes the insulation of the point C. This done, connect the wire E with the other pole of the coil and produce the spark. It is very easy, by moving the glass along, to make a number of holes as close to each other as may be desired. The only precaution necessary is to have the India-rubber plate large enough—so large that it will not be possible for the spark to jump between the wires by following the routes indicated by the dotted lines.


An Electrical Railway.—Mr. Werner Siemens exhibited an electrical railway at the recent exposition in Berlin, with which he attained a fair degree of success in transmitting electrical power to a distance, and applying it to the movement of carriages. This apparatus consists of a dynamo-electric machine fixed in the station supplying force to a second machine placed on a locomotive-carriage and connected with it by the rails of the track and a third rail which is insulated in the middle of the track. The electrical current is transmitted from the generating machine to the locomotive through the middle rail, and is returned through the wheels and the rails of the track. The carriages to be drawn by the locomotive are all electrically connected with it, so that communication is established through all the wheels. The train exhibited by Mr. Siemens consisted of the locomotive and three carriages with seats for six persons each. With this train and its eighteen passengers an effective force was gained equivalent to that of two horses. In the interior of the exposition building a force equivalent to that of three horses and a half was gained, and a speed of 7·8 miles an hour. Mr. Siemens, in giving an account of his invention to one of the societies a few months ago, did not seem to have much faith in its practicability, for he said he was afraid that "a great deal of water would run into the Spree before his dream would be realized," but his firm has since submitted to the city of Berlin a proposal for the construction of an elevated railway across a part of that capital, to be operated by his machines. A track is contemplated similar, in its elevation and relations to the street, to the tracks of the elevated railroads in this city. The carriages will be narrow and short, to contain ten sitting places and four standing-places. The machine to propel them will be placed under the floor of the carriage between the wheels, and a steam-engine with sixty-horse power, which will be employed in the production of the electricity, will be placed at the terminus. A speed of about twenty miles an hour is anticipated. The magistrates of Berlin have appointed a special commission of engineers and architects to examine into and report upon the proposal.


Insects in Libraries.—Dr. H. A. Hagen, of Harvard University, has given in the "Library Journal" some observations on "Insect Pests in Libraries." The principal insects which our libraries have to dread are the larvae of a beetle (Anobium), the same which is obnoxious to old furniture and picture-frames, which has been known for more than one hundred and fifty years, and the white ant. The beetle will eat through the thickest books, making a network of small passages, and, in some places, larger holes for its transformation. The white ants have been known for a long time in southern and western France, but did not appear especially injurious to books till about 1825, when they became very destructive. Some years later they did less damage, and at last disappeared without any apparent reason. These white ants exist in the United States, where instances of their destructiveness to books have been brought to notice in Springfield, Illinois, and in South Carolina. They are present at Cambridge, Massachusetts, in near neighborhood to buildings containing libraries. Mr. J. A. Lintner, of Albany, has noticed cases of cockroaches eating through the coating of the cloth binding of books stored in a basement; and the writer of this note has observed new books similarly injured by the common Croton-bug while they lay in a dry desk-drawer. The best remedy for insect depredations is constant use of the books. There are and must be in all complete libraries books which are used infrequently, and some which are very rarely used; and these afford good hiding places for the larvæ of the beetle. They may be killed without hurting the books, by putting the books under the glass bell of an air-pump and drawing out the air. After an hour the larvæ will be found to be dead. Constant attention is the only remedy against the white ants.


Relics of an Ancient Race in Eastern New York.—Mr. S. L. Frey describes, in the "American Naturalist," some relics of an ancient race which he has found at a place he does not name in eastern New York. A number of arrow-heads, and a small copper awl, square and of regular shape, which may have been used for a drill, had been found before at the same place. He discovered two tubes bored in cases of steatite, a sea-shell adapted to use as a drinking vessel, several bone awls, fragments of deer horn implements, a gouge made of bone, implements of horn stone, beautifully chipped and of perfect proportion, and other articles usual in such places. In another grave, what had apparently been a necklace or head-dress, composed of copper and shell beads, was found. The copper beads had been made of thin sheets of copper rolled into tubes; the shell beads, which were from half an inch to one inch and three quarters in length, and of an average diameter of about half an inch, were made from the columella; of large sea-shells rubbed and ground smooth, and drilled through their largest diameter. A similar necklace, but partly composed of small sea-shells, was found in another grave. The deepest grave was four feet deep, and contained one hundred and eighty-nine arrow-heads. It is especially mentioned that in two of the graves the bodies had been buried in an extended position.


A Chinese Hygieopolis.—According to Dr. W. Wykehara Myers, of the British Naval and Consular Service, Dr. Richardson has been anticipated in his "Hygieopolis," or city of health, and a city very like that which he has described as ideal is in existence at Wen-Chow, China. Dr. Myers is not prepared to say that the parallel is perfect, but observes that the similarity is so close as to warrant his alluding even to the high standard set up by Dr. Richardson. All the main and pleasant features of "Hygieopolis" above-ground were found at Wen-Chow, and even the deficiencies in the Chinese city did not prevent Dr. Myers from being surprised at the passing resemblance it presented to the ideal.


Animal Intelligence.—The following, cut from a recent issue of the "Portland Transcript," was sent to us by a valued correspondent, who vouches for its truth: "A friend gives us this dog-story as coming under his own observation: A bull-dog and a Newfoundland came into collision in Federal Street. The Newfoundland took to his heels for safety, and was closely pursued. Seeing that he was likely to be overtaken, he caught up a bit of dirt from the street, and at the critical moment dropped it as if it were something of value he was obliged to give up. The ruse succeeded; for the bull-dog stopped to pick up the supposed titbit, and the Newfoundland escaped. The disgust manifested by the vicious brute, when he found how he had been outwitted, h said to have been very comical."


Prehistoric Africa.—Dr. Emil Holub, the Austrian traveler, in a recent lecture before the British Anthropological Institute, on the central South African tribes, mentioned that he had found along the South African coasts clear traces of extinct tribes who, judging from their relics and from other indications, must have been of a very low type. Passing farther into the interior, there were evident relics of quite a different stage of culture, reminding him of the great African empire which the Portuguese marked on their maps as Monomatapa. Among them were workings of ancient mines, some even of gold, and the ruins of a rude kind of cyclopean fortifications. Such evidences, he held, pointed to exterminated tribes, and testified to the antiquity of the savage African rule of warfare, which destroys all the males, and allots the wives and children to the victors as slaves.


Production of Precious Metals in Colorado.—Mr. Frank Fossett, the author of a valuable work on Colorado, reports on the basis of his later observations, that that State has taken an immense stride forward in its mining industries during the past year, and has distanced California in the production of the precious metals. He believes that it will next year surpass Nevada and all other mining regions in the field of gold and silver. Full detailed statements have not yet been received from all quarters, but enough is known to make it sure that the return of the State for 1879 will amount to $18,650,000. The present rate of production is estimated at over $2,000,000 a month, with a prospect of a steady increase hereafter; and the entire product of 1880, it is believed, will be between 825,000,000 and $30,000,000. The product of last year consisted of 14,100,000 in silver, $3,000,000 in gold, $1,450,000 in lead, and $125,000 in copper.


The Carpet-Beetle.—Mr. A. S. Fuller contributes some notes to the "American Entomologist" on the habits of the carpet beetle, whose larva is commonly called the Buffalo-moth, which may be of help in finding a remedy for the ravages of the insects. The larvæ feed on carpets and woolens, but the fully developed insects feed and pair out of doors, after which the female returns to the carpets to lay her eggs. Mr. Fuller found the beetles last summer feeding on the pollen of spiræas, catching them for several weeks on these plants, but on no others in his garden. As the spiræas are very abundant in all parts of the country, it would be easy to plant a number of them around the house as a bait for the beetles, where, by watching them carefully, the insects may be killed. The small flowering species seem to be preferred by the beetles, and are therefore recommended, as the goat's-beard (Spiræa aruncus), sorb-leaved (S. sorbifolia), and meadow spiræa (S.ulmaria). They are, moreover, desirable plants for their beauty.