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Scientific American Supplement, No. 362, December 9, 1882试读：
GUSTAVE TROUVÉ.
The accompanying portrait of M. Gustave Trouvé is taken from a small volume devoted to an account of his labors recently published by M. Georges Dary. M. Trouvé, who may be said to have had no ancestors from an electric point of view, was born in 1839 in the little village of Haye-Descartes. He was sent by his parents to the College of Chinon, whence he entered the École des Arts et Metiers, and afterward went to Paris to work in the shop of a clock-maker. This was an excellent apprenticeship for our future electrician, since it is in small works that electricity excels; and, if its domain is to be increased, it is only on condition that the electric mechanician shall never lose sight of the fact that he should be a clock-maker, and that his fingers, to use M. Dumas's apt words, should possess at once the strength of those of the Titans and the delicacy of those of fairies. It was not long ere Trouvé set up a shop of his own, whither inventors flocked in crowds; and the work he did for these soon gave up to him the secrets of the art of creating. The first applications that he attempted related to the use of electricity in surgery, a wonderfully fecund branch, but one whose importance was scarcely suspected, notwithstanding the results already obtained through the application of the insufflation pile to galvano-cautery. What the surgeon needed was to see plainly into the cavities of the human body. Trouvé found a means of lighting these up with lamps whose illuminating power was fitted for that sort of exploration. This new mode of illumination having been adopted, it was but natural that it should afterward find an application in dangerous mines, powder mills, and for a host of different purposes. But the perfection of this sort of instruments was the wound explorer, by the aid of which a great surgeon sounded the wounds that Italian balls had made in Garibaldi's foot.
GUSTAVE TROUVE.
The misfortunes of France afterward directed Trouvé's attention to military electricity, and led him to devise a perfect system of portable telegraphy, in which his hermetic pile lends itself perfectly to all maneuvers and withstands all sorts of moving about.
The small volume of which we have spoken is devoted more particularly to electric navigation, for which M. Trouvé specially designed the motor of his invention, and by the aid of which he performed numerous experiments on the ocean, on the Seine at Paris, and before Rouen and at Troyes. In this latter case M. Trouvé gained a medal of honor on the occasion of a regatta. Our engraving represents him competing with the rowers of whom he kept ahead with so distinguished success. We could not undertake to enumerate all the inventions which we owe to M. Trouvé; but we cannot, however, omit mention of the pendulum escapement that beats the second or half second without any variation in the length of the balance; of the electric gyroscope constructed at the request of M. Louis Foucault; of the electro-medical pocket-case; of the apparatus for determining the most advantageous inclination to give a helix; of the electric bit for stopping unruly horses; and of the universal caustic-holder. He has given the electric polyscope features such that every cavity in the human body may be explored by its aid. As for his electric motor, he has given that a form that makes the rotation regular and suppresses dead-centers--a result that he has obtained by utilizing the eccentrization of the Siemens bobbin.
Although devoting himself mainly to improving his motor (which, by the way, he has applied to the tricycle), M. Trouvé does not disdain telephony, but has introduced into the manufacture of magnets for the purpose many valuable improvements.--Electricité.
TROUVE'S ELECTRIC BOAT COMPETING IN THE REGATTA AT TROYES, AUG. 6, 1882.
FRIEDRICH WÖHLER.
At the age of eighty-two years, and full of honor, after a life actively devoted to scientific work of the highest and most accurate kind, which has contributed more than that of any other contemporary to establish the principles on which an exact science like chemistry is founded, the illustrious Wöhler has gone to his rest.
After he had worked for some time with Berzelius in Sweden, he taught chemistry from 1825 to 1831 at the Polytechnic School in Berlin; then till 1836 he was stationed at the Higher Polytechnic School at Cassel, and then he became Ordinary Professor of Chemistry in the University of Göttingen, where he remained till his death. He was born, July 31, 1800, at Eschersheim, near Frankfort-on-the-Main.
Until the year 1828 it was believed that organic substances could only be formed under the influence of the vital force in the bodies of animals and plants. It was Wöhler who proved by the artificial preparation of urea from inorganic materials that this view could not be maintained. This discovery has always been considered as one of the most important contributions to our scientific knowledge. By showing that ammonium cyanate can become urea by an internal arrangement of its atoms, without gaining or losing in weight, Wöhler furnished one of the first and best examples of isomerism, which helped to demolish the old view that equality of composition could not coexist in two bodies, A and B, with differences in their respective physical and chemical properties. Two years later, in 1830, Wöhler published, jointly with Liebig, the results of a research on cyanic and cyanuric acid and on urea. Berzelius, in his report to the Swedish Academy of Sciences, called it the most important of all researches in physics, chemistry, and mineralogy published in that year. The results obtained were quite unexpected, and furnished additional and most important evidence in favor of the doctrine of isomerism. In the year 1834, Wöhler and Liebig published an investigation of the oil of bitter almonds. They prove by their experiments that a group of carbon, hydrogen, and oxygen atoms can behave like an element, take the place of an element, and can be exchanged for elements in chemical compounds. Thus the foundation was laid of the doctrine of compound radicals, a doctrine which has had and has still the most profound influence on the development of chemistry--so much so that its importance can hardly be exaggerated. Since the discovery of potassium by Davy, it was assumed that alumina also, the basis of clay, contained a metal in combination with oxygen. Davy, Oerstedt, and Berzelius attempted the extraction of this metal, but could not succeed. Wöhler then worked on the same subject, and discovered the metal aluminum. To him also is due the isolation of the elements yttrium, beryllium, and titanium, the observation that silicium can be obtained in crystals, and that some meteoric stones contain organic matter. He analyzed a number of meteorites, and for many years wrote the digest on the literature of meteorites in the Jahresbericht der Chemie; he possessed, perhaps, the best private collection of meteoric stones and irons existing. Wöhler and Sainte Claire Deville discovered the crystalline form of boron, and Wöhler and Buff the hydrogen compounds of silicium and a lower oxide of the same element. This is by no means a full statement of Wöhler's scientific work; it even does not mention all the discoveries which have had great influence on the theory of chemistry. The mere titles of the papers would fill several closely-printed pages. The journals of every year from 1820 to 1881 contain contributions from his pen, and even his minor publications are always interesting. As was truly remarked ten years ago, when it was proposed by a Fellow of the Royal Society that a Copley medal should be conferred upon him, "for two or three of his researches he deserves the highest honor a scientific man can obtain, but the sum of his work is absolutely overwhelming. Had he never lived, the aspect of chemistry would be very different from that it is now."
While sojourning at Cassel, Wöhler made, among other chemical discoveries, one for obtaining the metal nickel in a state of purity, and with two attached friends he founded a factory there for the preparation of the metal.
Among the works which he published were "Grundriss der Anorganischen Chemie," Berlin, 1830, and the "Grundriss der Organischen Chemie," Berlin, 1840. Nor must we omit to mention "Praktischen Uebringen der Chemischen Analyse," Berlin, 1854, and the "Lehrbuch der Chemie," Dresden, 1825, 4 vols.
At a sitting of the Academy, held on October 2, 1882, M. Jean Baptiste Dumas, the permanent secretary, with profound regret, made known the intelligence of the death of the illustrious foreign associate, Friedrich Wöhler, professor in the University of Göttingen. He said: "M. Friedrich Wöhler, the favorite pupil of Berzelius, had followed in the lines and methods of work of his master. From 1821 till his last year he has continuously published memoirs or simple notes, always remarkable for their exactness, and often of such a nature that they took among contemporaneous production the first rank by their importance, their novelty, or their fullness. Employed chiefly, during his sojourn in Sweden, in work on mineral chemistry, he has remained all his life the undisputed chief in this branch of science in German universities. This preparation and preoccupation, which one might have thought sufficient to occupy his time, did not, however, prevent him from taking the chief part in the development of organic chemistry, and of filling one of the most elevated positions in it.
"His contemporaries have not forgotten the unusual sensation produced by the unexpected discovery by which he was enabled to make artificially, and by a purely chemical method, urea, the most nitrogenous of animal substances. Other transformations or combinations giving birth to substances which, until then, had only been met with in animals or plants, have since been obtained, but the artificial formation of urea still remains the neatest and most elegant example of this order of creation. All chemists know and admire the classical memoir in which Wöhler and Liebig some time after made known the nature of the benzoic series, and connected them with the radicals of which we may consider them as being the derivatives comparable with products of a mineral nature. Their memoirs on the derivatives of uric acid, a prolific source of new and remarkable substances, has been an inexhaustible mine in the hands of their successors.
"This is not a moment when we should pretend to review the work which M. Wöhler has done in mineral chemistry. Among the 240 papers which he has published in scientific journals, there are few which the treatises of chemistry have not immediately turned to account. We need only confine ourselves to the discovery of aluminum, to which the energy and inventive genius of our confrère, Henry Deville, soon gave a place near the noble metals. United by a rivalry which would have divided less noble minds, these two great chemists carried on together their researches in chemistry, and joined their forces to clear up points still obscure in the history of boron, silicium, and the metals of the platinum group, and remained closely united, which each year only strengthened.
"The reader will pardon me a souvenir entirely personal. We were born, M. Wöhler and I, in 1800. I am his senior by a few days. Our scientific life began at the same date, and during sixty years everything has combined to bind more closely the links of brotherhood which has existed for so long a time."
OUR HEBREW POPULATION.
The United Jewish Association has made a canvass of the denomination in this country, finding 278 congregations, and a total Jewish population of 230,984. New York has the largest number--80,565. Then follows Pennsylvania, with 20,000; California, with 18,580; Ohio with 14,581; Illinois, with 12,625, and Maryland, with 10,357.
The Jewish population in the largest cities is as follows:
New York 60,000 San Francisco 16,000 Brooklyn 14,000 Philadelphia 13,000 Chicago 12,000 Baltimore 10,000 Cincinnati 8,000 Boston 7,000 St. Louis 6,500 New Orleans 5,000 Cleveland 3,500 Newark 3,500 Milwaukee 3,500 Louisville 2,500 Pittsburg 2,000 Detroit 2,000 Washington 1,500 New Haven 1,000 Rochester 1,000
This total Jewish population of 230,984 has six hospitals, eleven orphan asylums and homes, fourteen free colleges and schools, and 602 benevolent lodges. Of the free schools maintained by the Hebrews, five are in New York, four in Philadelphia, and one each in Cincinnati, St. Louis, Chicago, and San Francisco. Their hospitals are in New York, Philadelphia, Baltimore, Cincinnati, New Orleans, and Chicago, while their orphan asylums, homes, and other benevolent institutions are scattered all over the country.
THE MYSTERIES OF THE BAIKAL.
The Angara is cold as ice all the summer through, so cold, indeed, that to bathe in it is to court inevitable illness, and in winter a sled drive over its frozen surface is made in a temperature some degrees lower than that prevailing on the banks. This comes from the fact that its waters are fresh from the yet unfathomed depths of the Baikal, which during the five short months of summer has scarcely time to properly unfreeze. In winter the lake resembles in all respects a miniature Arctic Ocean, having its great ice hummocks and immense leads, over which the caravan sleds have to be ferried on large pieces of ice, just as in the frozen North. In winter, too, the air is so cold in the region above the lake that birds flying across its icy bosom sometimes drop down dead on the surface. Some authors say that seals have been caught in the lake of the same character as those found in the Arctic seas; for this assertion I have no proof. An immense caravan traffic is carried across the frozen lake every season between Russia and China. To accommodate this the Russian postal authorities once established a post house on the middle of the lake, where horses were kept for travelers. But this was discontinued after one winter, when an early thaw suddenly set in, and horses, yemschliks and post house all disappeared beneath the ice, and were never seen more. In summer the lake is navigated by an antiquated steamer called the General Korsakoff, which ventures out in calm weather, but cannot face the violent storms and squalls that sometimes rise with sudden impetuosity. Irkutskians say, indeed, that it is only upon Lake Baikal and upon this old hull that a man really learns to pray from his heart. The lake is held in superstitious reverence by the natives. It is called by them Svyatoe More, or the Holy Lake, and they believe that no Christian was ever lost in its waters, for even when a person is drowned in it the waves always take the trouble to cast the body on shore.
Its length is 400 miles, its width an average of 35 miles, covers an area of 14,000 square miles and has a circumference of nearly 1,200 miles, being the largest fresh water lake in the Old World, and, next to the Caspian and the Aral, the largest inland sheet of water in Asia. Its shores are bold and rugged and very picturesque, in some places 1,000 feet high. In the surrounding forests are found game of the largest description, bears, deer, foxes, wolves, elk and these afford capital sport for the sportsmen of Irkutsk.
Around the coasts are many mineral springs, hot and cold, which have a great reputation among the Irkutskians. The hot springs of Yurka, on the Selenga, 200 versts from Verchore Udevisk and not many miles from the eastern shore of the Baikal, which have a temperature of 48 degrees Réaumur and whose waters are strongly impregnated with sulphur, are a favorite watering place for natives as well as Russians and Buriats.--Herald Correspondent with the Jeannette Search Expedition.
TRAVELING SAND HILLS ON LAKE ONTARIO.
An interesting example of sand-drift occurs near Wellington Bay, on Lake Ontario, ten miles from Pictou. The lake shore near the sand banks is indented with a succession of rock-paved bays, whose gradually shoaling margins afford rare bathing grounds. East and West Lakes, each five miles long, and the latter dotted with islands, are separated from Lake Ontario by narrow strips of beach. Over the two mile-wide isthmus separating the little lakes, the sand banks, whose glistening heights are visible miles away, are approached. On near approach they are hidden by the cedar woods, till the roadway in front is barred by the advancing bank, to avoid which a roadway through the woods has been constructed up to the eastern end of the sand range. The sand banks stretch like a crescent along the shore, the concave side turned to the lake, along which it leaves a pebbly beach. The length of the crescent is over two miles, the width 600 to 3,000 or 4,000 feet.
Clambering up the steep end of the range among trees and grapevines, the wooded summit is gained, at an elevation of nearly 150 feet. Passing along the top, the woods soon disappear, and the visitor emerges on a wild waste of delicately tinted saffron, rising from the slate-colored beach in gentle undulation, and sleepily falling on the other side down to green pastures and into the cedar woods. The whole surface of this gradually undulating mountain desert is ribbed by little wavelets a few inches apart, but the general aspect is one of perfect smoothness. The sand is almost as fine as flour, and contains no admixture of dust The foot sinks only an inch or two in walking over it; children roll about on it and down its slopes, and, rising, shake themselves till their clothing loses every trace of sand. Occasionally gusts stream over the wild waste, raising a dense drift to a height of a foot or two only, and streaming like a fringe over the steep northern edge. Though the sun is blazing down on the glistening wilderness there is little sensation of heat, for the cool lake breeze is ever blowing. On the landward side, the insidious approach of the devouring sand is well marked. One hundred and fifty feet below, the foot of this moving mountain is sharply defined against the vivid green of the pastures, on which the grass grows luxuriantly to within an inch of the sand wall. The ferns of the cedar woods almost droop against the sandy slope. The roots of the trees are bare along the white edge; a foot or two nearer the sand buries the feet of the cedars: a few yards nearer still the bare trunks disappear; still nearer only the withered topmast twigs of the submerged forest are seen, and then far over the tree tops stands the sand range. Perpetual ice is found under the foot of this steep slope, the sand covering and consolidating the snows drifted over the hill during the winter months. There is something awe-inspiring, says the correspondent of the Toronto Globe, in the slow, quiet, but resistless advance of the mountain front. Field and forest alike become completely submerged. Ten years ago a farm-house was swallowed up, not to emerge in light until the huge sand wave has passed over.
RECENT IMPROVEMENTS IN TEXTILE MACHINERY.
At the recent exhibition at Boston of the New England Institute, several interesting novelties were shown which have a promise of considerable economic and industrial value.
Fig. 1 represents the general plan and pulley connections of the Harris Revolving-Ring Spinning Frame. The purpose of the improvements which it embodies is to avoid the uneven draught of the yarn in spinning and winding incident to the use of a fixed ring. With the non-revolving ring the strain upon the yarn varies greatly, owing to the difference in diameter of the full and empty bobbin. At the base of the cone, especially in spinning weft, or filling, the diameter of the cop is five or six times that of the quill at the tip. As the yarn is wound upon the cone, the line of draught upon the traveler varies continually, the pull being almost direct where the bobbin is full, and nearly at right angles where it is empty. With the increasing angle the drag upon the traveler increases, not only causing frequent breakages of the yarn, but also an unequal stretching of the yarn, so that the yarn perceptibly varies in fineness. The unequal strain further causes the yarn to be more tightly wound upon the outside than upon the inside of the bobbin, giving rise to snarls and wastage.
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