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Show SCIENTIFIC. ASTRONOMICAL PHOTOGRAPHS.-Dr. Henry Draper has lately been pushing his astronomical photography with great success. He has exchanged his 12 inch telescope for an 11 inch with a photographic correcting lens by Clark which performs admirably. He has succeeded in obtaining photographs of Polaris and Vega, with their so called companions-little stars very near the large ones; also of Jupiter and his satellites. In the case of Vega the image of the companion was brought out satisfactorily by twenty minutes' exposure, using a dry-plate process. DEPHOSPHORIZING IRON.-According to The Ironmonger, the dephosphorization process of converting pig iron has made such progress that the laborious and unhealthy process of puddling is likely soon to be superseded. Metallurgical experts differ as to the precise nature of the product of the pig iron dephosphorized in the Bessemer converter but all agree in regarding the material so produced as being certain to render puddled iron almost unnecessary. The ingot iron or steel made from phosphoric pig in the Bessemer converter is malleable, will weld, and bears severe tests for ductility contraction of area, etc. This being the case, finished iron should be materially cheapened when the process has made greater progress. In Germany dephosphorization is being conducted on a large scale, and now works, with a total capacity of 600,000 tons per annum, are being erected there and elsewhere on the Continent. ENTOMOLOGY.-A French entomologist J. H. Fabre, has recently published a most interesting work, entitled "Souvenirs entomologiques. Fludes sur Penstinet et les moeure des Insectes." It is written in a charming, attractive way. He has a good deal to say of the power insects have of finding their way to their nests. He tried experiments with sand wasps (Cerceris), carrying them over a mile away from their nests and marking them and letting them go. Five hours later four out of the twelve were found working at their barriers. He then carried nine of the wasps about two miles away, and the next morning released them in the market place of a town, but they rose above the houses and flew back to their nests. He then asks if memory enables them to traverse regions strange to them. "Evidently not. There can be no remembrance of the unknown." He thinks they have a special faculty, a kind of topographical sense, which we cannot appreciate. BOTANICAL.-The curious Maiden hair tree (Saluburia adiantifolus), also known in gardens by its Japan name of "Ginko," is the solitary survivor of an immense group of conifora which existed ages ago, and of which we find fossil remains all over the Temperate and Arctic Zones of the Northern Hemisphere. Professor Oswald, a learned German paleontologist, enumerates eight genera and sixty-one species of trees allied to this sole survivor that have already been found in a fossil state, and, though the experience of paleontologists shows that many supposed species eventually became united there will probably be enough new ones found, as the earth's crust becomes more thoroughly explored, to increase, rather than lessen, the number of species now recorded. It would be wise in this curious old survivor to study the modern principles of evolution, and give us a few more species by gradual modification, before the last summons shall come to join its fossil brethren. THE ELECTRIC LIGHT AS A MOTH CATCHER.-At a recent exhibition of agriculture and insectology at Paris, a medal was awarded to an exhibitor for a lamp especially designed to catch insects. It has since been shown that the electric light has great attractions for insects. A certain number of electric lights for ordinary illuminating purposes, were used this summer in the gardens of the Meaux Exhibition, in the vicinity of the Forest of Fontainebleau. No arrangements were made for catching the insects and they fell round the lamps, except a few that got admittance through the holes of the regulator. The number of the latter was so large that two of these lamps placed at a coffee stall in the open air had to be removed, all the carbons being covered by moths of every description. In a case in this city also the number of moths attracted by an electric light near the City Hall Park, on a summer's night, was so large that the constant stream of the insects seemed to surround the light with a white cloud. CHEAP GAS.-According to The London Echo, a remarkable invention has just been patented in France. For many years inventors have been trying to devise a means of utilizing water gas, but certain "finality prophets" pointed out that, as it cost as much to dissociate the gases forming water as they were worth as fuel when separated the research was much like seeking for perpetual motion. If report speaks ?? however, the problem has been solved by M. Paul Aube, who at one operation converts iron into steel and produces an illuminating gas. By a combination of the two processes he carbonizes the iron, and at the same time, obtains carburetted hydrogen, or the equivalent of coal-gas, at a merely nominal cost. The iron is placed in a retort with charcoal or coke, and, being raised to the proper temperature, is supplied with a dose of fatty matter, and subsequently, when steam is introduced, the latter is immediately decomposed, the oxygen uniting with the coke, and the hydrogen combining with the vapor of carbon, thus converting the iron into steel, and producing an illuminating gas at one operation. The cost of the process is more than covered by the difference in value of iron and steel, and the "gas" consequently represents only a portion of the clear profit. SUN AND STARS.-Prof. Proctor, the astronomer, after describing the variations in magnitude and brilliancy which have been observed to occur occasionally in stars reminds us that it is now a settled fact that each star is a sun like our own, and then he goes on to consider what would occur to the earth and its inhabitants in case our own sun should be affected as some of the stars have been. A tenth magnitude star in the constellation of the Northern Crown was in 1866 seen to shine as a second magnitude star-800 times its former lustre. He says: "If our sun were to increase ten fold in brightness, all the higher forms of animal life would be destroyed. A few animalcules might survive, and possibly a few of the lowest forms of vegetation, but nought else." Fortunately our sun has thus far only exhibited slight signs of perturbation-slight in comparison with the change which occurred in the star above referred to. Those who make a study of the sun's surface see that it is constantly changing, and that great commotions are occurring there from time to time. But within the history of mankind there has been no sudden increase in brilliancy and heat sufficient to destroy the denizens of the earth. Should such occur, the history of mankind would cease for a while at least. |