Popular Science Monthly/Volume 47/August 1895/Popular Miscellany

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Popular Science Monthly Volume 47 August 1895  (1895) 
Popular Miscellany
 

POPULAR MISCELLANY.

A Child's Thoughts about Providence. — A very instructive account of the mental aspects of childhood is given by Miss Isabel Fry, in a book called Uninitiated, one of the purposes of which is to show that it takes much longer for children to learn the real drift and meaning of the habits and expressions and feelings of their grown-up friends and attendants than it does to master the language in which those feelings are conveyed. She thus pictures the process gone through by a child in conceiving the meaning of God's constant observation and care of his creatures: "I was thinking dreamily about heaven, and how wonderful it was that God could always see me. Could he see, for instance, and did he notice that I had a button off my boot, or did he overlook some things and only trouble himself about that which was actually either good or naughty? I did not know. And then nurse said that he was always taking care of me every minute. Didn't he ever leave me alone at all? I supposed not. But surely if he saw that I was sitting on this chair, and knew that nurse had made up her mind not to come in for, say, twenty minutes, he might leave me at any rate for a little while. But no; I hardly thought he would. Then I went on to try to imagine what would happen. Supposing, for any reason, he did leave me. I should probably fall down through some vast open space and die. No, not exactly die, for then God would have to decide whether I was to go to heaven or hell, and I should be once more in his keeping, and in that case I should be just sitting here in the night nursery again for all the world, as I was doing at this moment. I could not make up my mind what would happen, and I felt it would be almost worth while to try the experiment." But if she should ask God to leave off taking care of her she might go so fast that she would not be able to pray him to take her back. But she would pray him to let her go for just one single second, and then take care of her again. After a long struggle with herself and much trembling, she did so — and nothing happened. "Breathless and motionless as I sat with eyes staring and ears strained, I could perceive no change whatever in myself or in my surroundings. The sewing machine in the nursery still purred on; little Samuel still knelt in the picture on the wall opposite me, with the yellow light still fiercely streaming upon him, and the bluebottle who had been keeping up a continual "fizzle" was still fighting on the window pane. I set myself rigidly, and tried again to feel the sort of falling or collapse which I had imagined. Still I felt nothing, and I had at last to give up the effort, and believe that for some reason, which perhaps I was not quite old enough to understand, God would not let go of my still sobbing body."


Science in Finland. — Besides the National University at Helsingfors, which had nineteen hundred and twenty-nine students in 1894, with the number increasing regularly, Finland has several scientific and other learned societies. The Finnish Society of Sciences, founded in 1838, has published, besides its regular volumes of transactions, a series of works on the nature, ethnography, and statistics of the country. Among its later achievements is the foundation of a central meteorological institute, which is assisted by the Government. It has, besides, taken part in a number of international polar POPULAR MISCELLANY.

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��expeditions, and has established a station at Sodankyla, in Lapland. Other societies are the Natural History Society (Societus pro faund et fiord fennicd), founded 1821 ; the Society of Finnish Literature, the Finno- Ugrian Society, the Finland Historical Soci- ety, the Finnish Archaeological Society, two geographical societies, a medical society, and a legal society. Among Finlanders distin- guished in science and letters have been LOnnrot, grammarian and collector of the national literature; Ahlqvet, another able grammarian ; Hallstrom, physicist ; the illus- trious astronomer Argeliinder ; the mathe- maticians Lindelof, Schulten, and Mittag- Loffler, the last editor of the international journal Acta Mathematica ; the explorer Nordenskiold, who removed to Sweden in 1857 to escape trouble on account of an ad- dress he had made at a students' festival ; the botanist Nylander ; the zoologist Nord- mann ; and the surgeon Estlander. Swedish literature is also distinguished by several Finnish names of great writers ; Finnish literature is very ancient, although it has only recently begun to receive special atten- tion. The later poets and romancers have discussed in the fresh and spontaneous old poetry of the ancient folklore a nearly in- exhaustible mine of rich images and striking epics. Finland has further produced emi- nent artists in various lines. The full story of the achievements of this too little known country of the far north is told in the book La Finlande au XIX siecle, which the writ- ers and artists of the country have combined to make up, published at Helsingfors, in French, in 1894.

Report on Opium. The opium commis- sion appointed many months ago by the British Government was charged with the investigation of three questions whether opium, when taken in moderation, is injuri- ous ; whether Indian opinion is opposed to its use ; and whether prohibition is a prac- ticable policy. The commission has pub- lished its report, and declares that by a vote of eight to one it answers all the three ques- tions in the negative. The commission finds that an immense number of doctors in In- dia believe opium to be less injurious than alcohol. Witnesses drawn from every grade and class testified that it is an excellent

��remedy against malarial fever ; that it can be and is consumed in moderation all through life; and that its effect upon the constitu- tion in health is practically nil. Among natives the belief in the value of the drug is nearly universal. The practice of opium- eating pervades every class, is considered allowable by every class, and the people are opposed to prohibition. The commission, therefore, though they believe some improve- ment in the restrictive laws may be possible, refuse to suggest any, and advise substan- tially that the present system be left alone.

Steel Buildings. A steel building, as the words are now used by builders, is a struc- ture supported by a steel frame, which frame should carry all the other materials used in the construction. If the frame is so ar- ranged that it will always hold the building securely in the position and condition in which it was first erected, the other materials used in construction will be required chiefly to perform some other office than that of giving strength and support. As considered by Mr. C. T. Purdy, in his paper on the sub- ject, the most important difference between the old brick and stone buildings and the new steel ones is in the construction of their exterior walls. Brick and stone in the older forms of construction were used first of all to make the building strong. In steel build- ings this use of masonry has nearly disap- peared. It is used instead only to inclose the structure from the outside air and ele- ments, to protect the frame from fire, and to afford opportunity for architectural effects. Thick walls are useless with these frames, and no matter how high the building is, the exterior walls do not need to be heavier at the bottom than at the top. Openings may be made in them in almost any way or of any size. In some respects the larger they are the better, and the wall in any story may be removed without injury to that above or below. This is a great change. The steel frame has worked a great difference in the concentration of loads. Walls tend to dif- fuse and spread the loads which they carry. They act as beam and column at the same time, and it is not always easy to tell what part of the foundation supports a given load in the upper part of the building. With the column construction this indefinite feature

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��becomes definite, for all the loads are sure to be concentrated at the column centers that carry them. Kindred to this change is the large independence of partition walls which the steel construction makes possible. Another radical change, and the most con- spicuous to the eye that steel has introduced, is in the height of large buildings. Steel buildings their construction admitting of unlimited bracing may be carried to any height, the only restrictions being those im- posed by the character of the foundations, the land, and economical considerations. The steel construction admits a vast increase of window space, the masonry walls which had to be built for strength being no longer re- quired, and their place may be taken by glass.

The Weather and Mental Aetion. Who

has not felt the difference between a de- pressing and an exhilarating day? Sydney Smith wrote : " Very high and very low tem- peratures establish all human sympathy and relations. It is impossible to feel affection above seventy-eight degrees or below twenty degrees." Dr. Fair and Dr. Stark almost lead us to think morality is registered on the thermometer, so surely does it measure cer- tain kinds of criminality. On suicides the effects of the weather are well known. Nearly all vocations are affected by weather. Men of science are often as much subject to weather as seamen. Some writers must have the weather fit the mood, character, or scene. If one will read poetry attentively, he will be surprised to find how many weather marks are scattered through it. Diverse weather states may be one cause of so much diversity and even disagreement in thought processes usually regarded as scientific. Many experi- enced teachers think there should be modi- fications of school work and discipline to correspond with the weather. The head of a factory employing three thousand workmen has said, " We reckon that a disagreeable day yields about ten per cent less work than a delightful day, and we thus have to count this as a factor in our profit and loss ac- count." These are some of the ideas put forth in a preliminary statement by J. S. Lemon, who proposes to publish more at length upon the subject. "Laboratory in- vestigation of the subject," he says, " meets

��at the outset the difficulty of distinguishing results of weather changes from similar states otherwise caused. This difficulty is no greater than in many other topics of research, and we believe will not invalidate our methods and results."

Characteristics of Recent Geological Stndy. If one were asked, says Sir Archi- bald Geikie, to specify the feature which above all others has marked the progress of geology in Britain during the past five and twenty years, he would reply, the enlarged attention given to the study of the rocks, or petrography ; and this study has been revo- lutionized by the introduction of the micro- scope as an adjunct to research. The rocks of the country have become a foremost ob- ject of study. In stratigraphical geology a much closer attention than ever before has been given to the investigation of the most ancient accessible parts of the earth's crust. The fundamental platform on wdiich the fos- siliferous rocks repose has been searched for and has been detected in several places where it was not before supposed to exist. We know more clearly than before the gen- eral outlines of two or more great geological periods anterior to the earliest relics of ani- mal life. Among the applications of pale- ontology to the stratigraphical side of geology the most important in recent times has been the recognition of life zones among the stratified formations and the adoption of these as a clew to the interpretation of the sequence of strata, and even under some risk of error of tectonic structure. In the de- partment of geotectonics one of the most interesting features has been the increased attention bestowed upon the nature and results of the great movements that have affected the crust of the earth. Another distinguishing characteristic of the period has been the increased interest taken in the history of the earth's surface or its super- ficial topography as contrasted with the al- most exclusive attention given by the older geologists to the story of the rocks. The views respecting the possible age of the earth have undergone several modifications by geologists and physicists alternately, with accepted periods ranging from four hundred millions down to ten millions of years. The latest phase of them is that put forward by

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��Prof. Perry from the physical side, that, on the assumption that the earth is not homo- geneous, as Lord Kelvin supposed, but pos- sesses a much higher conductive and thermal capacity in its interior than in its crust, its age may be enormously greater than previous calculations have allowed.

Modoc Songs. During his talks with Modoc Indians, Mr. Albert S. Gatchett has been able to record from dictation a number of curious songs which these people highly, appreciate, and frequently sing while at work and while sitting idly in their lodges. Only a few of them are lugubrious, but the majority are merry utterances of a mind free from care. There are erotic songs, dance songs, satiric and mythologic songs, all de- livered in a way that is half spoken and half sung. Some, however, have attractive and elaborate melodies, which, if well arranged for the piano or string instruments, would doubtless produce a sensation in cultured communities. A specimen is given of a song which is introduced as sung or spoken by a prairie owl, which has the faculty of turning its head around and then turning it instan- taneously to the normal position ; while, when it draws its body up, it appears almost ball-shaped, and when traveling over the prairie seems like a light-colored ball rolling over the ground. The man singing the song is supposed, after throwing off his garments and limbs, to appear also as a head only, and rolls on for many miles, when he may be seen partaking of food inside of his subter- ranean lodge. He has a dog who faithfully tries to gather up his discarded appendages, and take them first to his master and then home. With this is coupled an idyl of a young man carrying his sister on his back to her bridegroom, and leaving her close to a pine tree. A cradle song describes the hab- its of the robin, which is seen earlier than other birds flying toward the cedar to pick at the bark in search of ants ; the mothers tell their babes that robin redbreast sings this song to its young, and sometimes also to its grandmother. A third song has a satirical application to another town than that of the singers.

Uses of Science Teaching. Dr. Michael Foster defines two uses for the teaching of

��science in schools. The first he calls the " awakening " use, and the second the more distinctly " educational " training use. The minds of the young being differently consti- tuted, one mind is especially awakened by one branch of knowledge, another by an- other. Physiology serves as awakening knowledge to a large enough number to make it desirable to teach it. For this purpose it should be taught " as a new independent sub- ject, not demanding any previous knowledge. It should be presented as a wholly new field, into which the mind may wander at will without any restrictions as to being qualified for entrance. It also follows that the teach- ing must be of a most elementary kind ; that as much of chemistry or physics as is neces- sary for the comprehension of the physio- logical matters should be taught with the physiology, and, as it were, a part of it, the pupil being led into chemistry and physics by his interest in physiology, and not being com- pelled to learn the one, for which he or she perhaps does not, at present at least, care, before beginning the other. The instruction given, however elementary, should consist in part of demonstrations and practical exer- cises." In this way, Dr. Foster would have physiology very widely taught, but not made a compulsory study. As a distinctly educa- tional study, as a training for the mind, he regards it as unsuitable for schools.

American Life Zones. Six life zones of animals and plants are described by C. Hart Merriam, in his Ornithological and Mamma- logical Report to the Department of Agricul- ture, as having been defined in this country north of the tropical zone. They may be grouped under the two heads of northern or boreal, and southern or austral. The Arctic or Arctic Alpine zone is above the limit of tree growth, is the home of the polar bear, arctic fox, reindeer, etc., and has no agricul- tural importance. The Hudsonian zone com- prises the northern or higher parts of the great transcontinental forest, and is likewise of no agricultural importance. The wood- land caribou and the moose are probably its most striking animals. The Canadian zone, comprising the southern or lower part of the great transcontinental coniferous forest, is the first zone, coming from the north, of any agricultural consequence. It has its charac-

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��teristic animals, and in it white potatoes, tur- nips, beets, the Oldberg apple, and the more hardy cereals may be cultivated with mod- erate success. In the Transition zone, the outlying boreal and austral elements over- lap ; the forests and the fauna are mixed, and northern and southern trees and animals grow and live side by side. In this zone we enter the true agricultural part of our country, and the hardier crop plants attain their highest perfection. In the Carolinian zone trees adapted to a warmer climate, like the sassa- fras and tulip tree, first make their appear- ance, and the semi-hardy fruits, the sweet potato, tobacco, and the hardier grapes reach their best conditions. In the Ausiro -riparian zone, the long-leaved pine, magnolia, and live oak are common on the uplands, and the bald cypress and cane in the swamps ; the animals and birds are characteristic. This is the zone of the cotton plant, sugar cane, rice, pecan, and peanut, and of tender fruits. Still farther south is the Tropical region, which in the United States is restricted to southern Florida and extreme southeast Texas, along the Rio Grande and the Gulf coast. The Division of Ornithology and Mammalogy is engaged in tracing the courses of these re- gions across the continent, and in the prepa- ration of large scale maps on which their boundaries are shown in different colors.

Antillean Elevations and Depressions.

A study by Charles Torres Simpson, on the distribution of the land and fresh-water mollusks of the West Indian region, touches upon the evidence they afford with regard to past changes of land and sea. The author finds that a considerable proportion of the land snail fauna of the Greater Antilles seems to be ancient and to have developed on the islands where it is now found. There appears to be good evidence of a general ele- vation of that region after most of the more important groups of snails had come into existence, at which time the larger islands were united and a land connection existed with Central America by way of Jamaica, and a considerable exchange of species went on between the two regions. At some time during this elevation there was probably a landway from Cuba across the Bahama pla- teau to the Floridian area, over which cer- tain groups of Antillean mollusks crossed.

��This period was followed by one of general subsidence, during which Jamaica was first isolated, then Cuba, and afterward Hayti and Porto Rico. The connection between the Antilles and the mainland was broken, and the Bahama region, if it had been previously elevated above the sea, was submerged ; the subsidence continuing until only the summits of the mountains of the Greater Antillean islands remained above water. Then followed another period of elevation, which has lasted, no doubt, until the present time, and the large areas of limestone uncovered in the Greater Antilles furnished an admirable field for the development of the groups of land snails that survived on the summits of the islands. The Bahamas have appeared above the surface of the sea, either by elevation or growth, and have been peopled by faunas drifted from Cuba and Hayti, and a number of land and fresh-water species have been colonized in south Florida. The Lesser Antilles have been peopled for the most part from South America.

Smoking in Mashonaland. The luxuries indulged in by the Mashonas appear, accord- ing to W. A, Eckenberg, of the railroad sur- vey, " to be confined to tobacco not usually smoked, but taken as snuff and beer manu- factured from the seed of the millet. Drunk- enness is an uncommon vice, except among certain of the chiefs. In the coast districts hemp is smoked in a hookah pipe of simple construction. A long, narrow gourd forms the body of the pipe. Halfway down it a hole is made of a convenient size for apply- ing the lips. The gourd is filled with water halfway to the level of the hole. Through the closed top is inserted a small hollow reed, reaching nearly to the bottom of the water, and protruding well beyond the upper end of the gourd. To the upper end of the reed is fixed the clay or stone bowl of the pipe, and this is of very small size, capable of holding only a sufficient quantity of hemp for a few whiffs. The smoker, holding the gourd upright to prevent the escape of the water, applies his lips to the hole, and draws the smoke to his lungs, through the water, by two or three vigorous inhalations. The result is made known to the whole neighbor- hood by a violeut and apparently purposely exaggerated coughing and spluttering ; the

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��louder the cough, the keener appears to be the enjoyment of the smoker and his com- panions. The pipe is passed round, until the whole of the smokers are engaged in violent contortions, accompanied by an al- most terrifying coughing."

Aboriginal Art in Copper. Very inter- esting specimens of objects made of wood and covered with copper have been found among the relics of the American aborigines. Several have been described by Prof. F. W. Putnam and by Warren K. Moorehead, both of whom have found them in Ohio. Other objects have been found of copper sheathed with silver, gold, or meteoric iron. It is shown clearly that the American aborigines in the Mississippi Valley and in South Amer- ica had the art of cold-hammering copper, of beating it so as to overlie and fit upon a warped or curved surface, and of turning the edges under. Yet more elaborate work is exhibited in two specimens sent to the Na- tional Museum by Lieutenant G. T. Emmons, United States Navy, of figures of humming- birds in wood, well carved and painted red, each wing and tail of which is overlaid with a covering of sheet copper, pressed down to fit and turned under at the margins so as to be held fast. The surfaces are adorned with the conventional wing and eye signs of the Haidas. Especial attention is invited by Mr. Otis T. Mason to the carving on the copper. The furrows and ridges are all cut with steel tools. The work is regarded by Mr. Mason as " above and beyond the ability of the aboriginal metallurgists of the Mississippi Valley."

Korean Hats. The hats of the Koreans are described by Mr. H. S. Saunderson as shaped somewhat like inverted flower-pots, with broad, straight brims, measuring nearly two feet across ; while the crowns are about six inches high and three inches in diameter at the top. " The shape is undoubtedly due to the way the hair is dressed. These hats are made of horsehair or very finely split bamboo, beautifully plaited, and are var- nished, as a protection against the weather. They are invariably stained black, except for half mourning, when they are string-color (that is, of natural hemp). They are usually fitted with bands which are tied under the

��chin, but in the case of high officials these bands are replaced by a long string of beads joined at each end to the hat. This hat does not fit upon the head itself, but rests upon a tightly fitting skullcap, held in place by strings tied round the head. The natives are very careful of their hats, for they are expensive, and when it rains they always protect them with little coverings of the oiled paper for which the country is famous, and of which they make their waterproof coats, tobacco pouches, and fans. The officials, when on court duty, wear even more extraor- dinary hats than these, but their shapes are so fantastic that it is perfectly impossible to describe them. In the winter, fur and wadded head-dresses are worn under the hats. . . . The official servants wear hats made of black or brown camel's-hair felt with small round crowns and large flat brims ; while those worn by the soldiers are much the same in shape as the gentry's, but are made of black felt, have much smaller brims, and are bound with red." The most curious hats are those of the mourners, shaped like enormous toad- stools, and so large as to hide the face. They are made of plaited bamboo strips, and are not colored. The women wear nothing on their heads, except in winter, when they put on curiously shaped fur caps, open at the crown and adorned in front and behind with red silk tassels.

Uses of Wire. Wire is shown in Mr. J. Bucknall Smith's book on its manufacture and its uses, to be employed for a great variety of purposes, and these having a very extended range. It is used for the delicate hair springs of watches, and in the form of large cables supports suspension bridges. It is also used in the manufacture of pins, needles, and fish- hooks ; it has been applied in coils to the construction of heavy ordnance, and it forms the periphery of a huge fly wheel recently constructed in Germany. Wire ropes are valuable in supplying the means of haulage in mines ; by their help materials are trans- ported in the air over a rough country ; they are used for the traction of tram cars, and of barges along canals ; and, being stronger, lighter, more durable, and cheaper, they ad- vantageously replace hempen ropes for tow- ing, moving, hoisting, and other purposes. Filigree work is formed of fine silver and

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��silver-gilt wire ; the finest wires are inserted to serve as tbe hairs within the eyepieces of the telescopes of surveying and astronomical instruments ; and wire is largely used in fencing and netting. Steel wire forms the frames of spectacles, and has replaced whale- bone in the ribwork of umbrellas. It is also employed for the strings of pianos and other musical instruments, and has found a more recent application in the spokes of cycle wheels. Copper wire forms the coils round the magnets of dynamo machines for gener- ating electricity, and it transmits the electric current to a distance after its production, for the purposes of illumination. It, moreover, furnishes the vehicle for the transmission of messages by the telegraph and telephone ; and when inserted in submarine cables it forms a connecting link between distant parts of the world, and permits the firing of un- der-water mines in security by an electric bat- tery at a distance. The great diversity of uses to which wire is applied is due to the in- creased tensional strength possessed by metals when drawn into wire, which is owing to the great tensional resistance acquired by the outer skin ; to the flexibility, combined with strength, possessed by wire cables ; to the facility with which wire can be drawn out to a variety of gauges ; and to the extreme fineness that can be attained with certain metals in the process of wire drawing.

Cereals in Japan. The most important cereal crops of Japan, according to a report recently issued, are rice, barley, and wheat. Rice is cultivated in nearly all the provinces, and, either as flour or whole grain, boiled with rice, is a common food. It is whitened like pearl barley, steeped five or six hours in water, and then boiled. One of the most common articles of food is miso, which is prepared by pounding together boiled soy beans, salt, and the koji or yeast, prepared from common barley. Barley is also used for brewing beer and making confectionery, and as food for horses and cattle. Its straw, bleached and plaited, is used in summer hats. Wheat is also generally cultivated, and is principally used for preparing soy, vermicelli, and confectionery, and its straw for thatching roofs, etc. Some barley and wheat is exported to foreign countries, barley chiefly to Hong Kong and Vladivostock,

��and wheat, in flour, to Russia and Korea, and as grain to Hong Kong and England. The manufacture of straw plaits and other goods from bleached barley stalks is assum- ing large proportions. Although Japanese straw is not so good as that of Italy, it is better than that of China. Articles of straw, especially toys, have been made for many centuries, but recently, stimulated by the demand for exportation, the manufacture of plaits has increased rapidly.

Chitral. Chitral, where the British re- cently conducted a successful military cam- paign for the relief of their post, is described by Captain Younghusband as " a mountain- ous country, which, if you could get a bird's- eye view of it, you would see to be composed partly of gigantic snowy peaks, partly of barren rocky mountains, and, in a very small degree, of cultivated land. The valleys are narrow and confined, the main ones in their inhabited portions running from five thou- sand to eight thousand feet above sea level. It is only in them that any cultivation at all is found, and even there it is not carried on very extensively. But what there is is gen- erally very good, and Chitral is a country noted for its fruit." All the ordinary cereals are grown, though in the higher part of the valleys it is only possible to produce barley and buckwheat. The whole food production is small, and barely suffices for the people of the country. The climate varies, of course, according to the height of the valley. The population of Chitral is probably about sev- enty thousand or eighty thousand. The peo- ple are all Mohammedans, but not of a very strict or fanatical type. In the lower part of the Chitral Valley, where they touch on the Pathans, so noted for their fanaticism, they have become to a certain extent tainted by it ; but in the upper valleys the people are very quiet, and do not seem to trouble them- selves much about religious observances. On the whole, the Chitralis may be described as a peaceable race, who can fight well enough when they are roused to action, but who really prefer to keep quiet and be left alone to enjoy life in peace. They are very fond of sport, and delight in polo, which they play in an offhand, " go-as-you-please " way. The ruler of the country is designated the Mehtar, and has absolute power up to a cer-

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��tain point, beyond which he is hedged in by custom ; and nearly all the affairs of state are transacted at the audience hall, where every man has his say and perfect freedom. The state is situated between Cashmere and the Hindu Kush Mountains.

Making the Ilonse Healthful. The re- lation of the house to the prevention and treatment of disease is set forth by Dr. G. V. Poore, in The Practitioner, as a matter of prime importance. The danger of the com- munication of infectious disease to the other inmates of the house in which it appears has long been recognized, and the list of diseases communicable in this way is ex- tending ; yet sufficient account of this danger is seldom taken in planning and construct- ing the dwelling. The main object to be kept in view in building a house, and espe- cially in building a house for invalids, is the supply of fresh air. Too much care can not be taken to insure that all the channels of internal communication hall, passages, stair- cases have independent ventilation of their own. Unless there be means of getting these internal channels blown out by through draughts, the house can not be wholesome; and in the event of any air-borne contagion getting a footing in the house, the liability to spread is enormously increased. These in- ternal channels must have light also. If the house be of several stories, the ventilation of the staircase has an importance that bears a direct proportion to the height of the house. The shafts for elevators require in- dependent ventilation as much as the stair- cases. One of the chief defects in the con- struction of city houses is the absence of provision for effective ventilation ; so that the internal channels of communication, in- stead of serving for the supply of fresh air, merely facilitate exchange of foul air. This defect of construction is dangerous in proportion to the size of the building and the number of persons it contains. The sug- gestion has been made to place the sec- ondary staircase (in invalid homes) between the wards and the sanitary offices, so that the staircase well forms a cut-off, with cross- ventilation between the ward on one side and the various sinks, closets, and baths on the other side. The point which requires more attention than any other in building

��a house is the aspect. This is too often neg- lected. A house should receive its maxi- mum amount of sun. The best aspect for a house is generally conceded to be that which allows its chief rooms to look to the southeast. In this way the morning sun is enjoyed, and the rooms do not get the glare of the afternoon sun. It may be advisable to build a house in the form of a veritable sun-trap. The sanitary advantage of a large area for a house is very great indeed. In hospitals we now recognize that infinitely the most important element of the "cubic space per bed " is the floor area, and that a deficient floor space is not to be compen- sated for by giving great height to the wards. The same reasoning is applicable to a house.

Irrigation of the Nile Valley. In pro- jecting the irrigation works for the Nile Val- ley Engineer Scott-Moncrieff first undertook to restore the barrage built by Mohammed Ali two stone bridges of seventy-one and sixty-one arches respectively thrown across the Rosetta and Damietta branches where they bifurcate. The arches were intended to be fitted up with gates, by lowering which the water would be dammed up and turned into three great brick irrigation canals. The idea of these works was excellent, but the execution was feeble, and they had so far failed to accomplish their purpose. They were again taken in hand and completed in 1890, since when the barrage has given no trouble. The three great canals carry off all the river supply from above it, so that prac- tically now the low Nile is emptied every season at the barrage, and no water escapes to the sea. Attention was next directed to providing for the storage of the surplus waters of the upper Nile. The first scheme was to build a great dam at Philse, to be one hundred and fifteen feet high, eighty-five feet at the base, and a mile and a quarter long, pierced by sluices large enough to allow the whole Nile at highest flood to rush through. The lake formed would have been one hun- dred and twenty miles long. The execution of this plan would have drowned the island of Phila) with its splendid Ptolemaic tem- ples built on the sites of older buildings that disappeared centuries ago ; and the civilized world protested against the vandalism, though

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��THE POPULAR SCIENCE MONTHLY.

��it were perpetrated in the name of public utility. Even the French for once agreed with the English about what should be done in Egypt. The plan was changed. The ma- jestic structure of the dam will be cut down thirty-seven feet, so as to be only eighty-eight feet high, and Philas will stand in a lake, but will not be drowned.

Patiuas of Japanese Bronzes. Describ- ing the patinas of Japanese bronzes, Mr. W. Gowland, late of the Imperial Mint, says that in many bronzes the beautiful color is due to a " stain " or colored film of infini- tesimal thinness. In others, the surface of the metal is altered to a considerable depth, and in these only we have true patinas. Fre- quently both a stain and a patina are pro- duced by similar treatment, but the opera- tions required for the latter are of a more prolonged character than for the former, and are accompanied by special manipulations in addition to the application of what are called pickling solutions. For the production of patinas of the richest and darkest shades of brown by Japanese methods, it is essential that lead should form one of the constituents of the bronze, and that zinc should either be absent altogether or be present only in small proportions. On the other hand, stains of any color can be given to metal of any com- position, and even to unalloyed copper. The substances used in the operations are cop- per sulphate, basic acetates of copper (verdi- gris), iron sulphate, sulphur in fine powder, alum, vinegar prepared from unripe plums, and a decoction of the roots or entire plant of Calamagrestis Hakcnensis (natural order Graminece), potassium nitrate, and sodium chloride. The most important of these re- agents are the first five. The processes for producing a patina by the use of the various solutions of these substances are somewhat complicated and difficult, and the interme- diate operations, on which its production de- pends more than on the exact composition of the solution, are variously modified in differ- ent foundries.

The Peril of Color-Blindness. Renewed attention has been called by Surgeon W. M. Beaumont, of the Bath (England) Eye In- firmary, to the importance of perfect color vision for railway servants, which is unques-

��tioned in the minds of ophthalmic surgeons, however other doctors and railway directors may be disposed to ignore it. Some ques- tions asked by one of the doubting doctors, whether, since attention has been turned to the subject, any accident has been brought home to defect in color vision, or other facts demonstrating the theory have been brought out in usual practical sailing and railway life, are answered by reference to several illustrative incidents that have been gath- ered. Of these are the wreck of the steamer City of Austin, on the Florida coast, with a color-blind pilot ; the collision of the Corbet Castle and the T. H. Ramieu, due to the color-blindness or short-sightedness of the chief officer ; the collision of the Lumber- man and the Isaac Bell, near Norfolk, Va., the Lumberman's master being color-blind, and consequently taking the wrong course with his vessel ; and the narrow escape of the steamer Neera from a collision through the color-blindness of its officer. In an- other instance the color-blindness of a rail- way fireman and the imminent danger of collision thereby were experimentally deter- mined in the ordinary working of the train. Even where the color-blind engineer believes he can distinguish between the signals, and appears to do so, he does it, not by the color, but by the difference in intensity. This is a very uncertain and indefinite factor, and is liable to variations according to the weather, the condition of the engineer, and other causes not so well known, and can not be safely depended upon.

Farming on the Yang-tse Kiang. The

country in China along the Yang-tse River from Shanghai to Hankow, and for a hun- dred miles on either side of the river, is, in general, a rich alluvial plain, traversed by ranges of hills having an east and west trend. The tops of the hills give the best tea, and where the ground is stony fir and oil trees are planted, for oil, resin, timber, and fire- wood. On lands of intermediate height or where the land is not suitable for rice cot- ton, wheat, corn, buckwheat, sweet potatoes, and kitchen vegetables are grown in great profusion. Dairy farming is unknown, and milk is looked upon with disgust. The na- tive buffalo is the domestic animal employed in cultivating rice. Three crops can geuer-

�� � generally be secured in a year. A little indigo is grown for domestic use, and almost takes care of itself. In many respects the bamboo takes the place of metals, although iron, copper, and brass are well known, and have been from very early times. The young shoots make an excellent vegetable, and paper and twine of great strength are produced from the fiber. The fields are cultivated like gardens, well hoed and clear of weeds. All the tools with cutting edges are of native manufacture, and steeled and tempered on the edge.