[Translated or the Scientific American from “ Aus der Natar.”] The presence of traces of copper in the blood of the lower animals has been for years an undisputed fact among chemists. In the blood of the higher animals, however, with few exceptions, no copper has been detected until lately. Wack-enroder, for instance, discovered tins metal in the blood of the duck, but not in that of the ox, the sheep, or the chicken. Its presence in the blood and in the muscle of the flesh of man has been asserted as often as it las been denied, and now, as there is no doubt that it sometimes occurs in the bile, and bile stones, and the liver of man, itsexistence in these organs is still considered to be merely accidsntal, the more so as it is well known they retain poisonous substances more than other organs. Some years ago, Mr. Ulex, in Hamburg, was led to search for copper in various animals by the following accident. From the 17th to the 19tn of May, 1865, a dozen wild beasts died suddenly in the zoological garden in Ham burg. There being suspicion that they had been poisoned, a chemical examination of the intestines was undertaken. However, no well-known poisons could be discovered, except copper. The beasts had been fed with the flesh of a horse the day before, and, there being still some left, it was also subjected to examination. There being copper found, Ulex expected to be able to conclude his researches by the proof of the absence of copper in the flesh of a healthy, freshly-killed horse. To his great surprise, however, this metal occurred also in this case, indeed, in the most undoubted manner. A piece of beef having been examined with the same result, it gave rise to the supposition of a general distribution of copper in the animal kingdom. As the tests for copper are very easy and simple, as well as exceedingly sensitive, if properly applied, the respective investigations were extended by Ulex to animals of various zoological classes. The reagents employed were tested for copper in every case, and rejected if containing any. Ulex proved the existence of this element in the yolk of eggs, and in bath sponges. The quantity ranged from 001 to 0'10 per cent. Among the mammalia, it was found in the stomach and intestines of the European and Canadian lynx, and in those of some species of the leopard, jackal, and repeatedly in the flesh of horses and cattle. It was met with in Liebig's meat extract, which, as is well known, contains the soluble portions of beef in a concentrated form. Moreover, it was discovered in the breast of a " crick duck," in the yellow and white of an egg, more so in the latter than in the yolk. Among amphibials, in the geometrical tortoise, the viper, and frog. Among fishes, it was met with in the eel and torsk, and among animals of the lower classes, copper was met with in the following species : In Crangon vulgaris, the South American bird-catching spider, Scolopendra Italica, in the Spanish fly, the earth-worm and the ascaries, in the edible vino-snail, in sea stars, in the thick-hided echinanthus, and in the bath sponge. It is thus seen that copper was detected in every case where it had been searched for; this having been the case with accidentally chosen animals of various zoological classes, it may rightly be concluded that the mefal copper, like iron, is of a general distribution in the animal kingdom. From this it follows that copper must also be present in plants, inthe ground,and in the sea. Indeed, copper was detected in plants by Meissner and John more than fifty years ago, and later it was ascertained by Sarzeau to be present in more than five hundred vegetable species. In the earth, copper has been repeatedly detected, and so in the water of the ocean by Durocher, Mala-guti, Field, and Piesse. If copper is found in the vegetable fiber, it follows that it must also ba present in its industrial products. In order to ascertain this, Ulex selected a material that is daily employed by chemists, and, on account of its purity, highly esteemed by them, namely, Swedish filtering paper. Upon, analysis it was found that ten grains of it yielded 6'03 grains or 6'3 per cent of ashes, from which a piece of copper half tlie size of a pin's head could easily bo obtained. Charcoal also yields a cupreous ash, and as both paper and charcoal are made use of in the analyses spoken of, it might be suggested that the copper of these substances got into the analyzed materials, where, of course, they would have been found. Yet, this reaction has its limits. If it is possible to detect copper in ten grains of paper, and in a hundred grains of charcoal, it is not possible to find it in 025 grains of paper, or O'l grain of charcoal, which are the quantities used in each analysis. Besides, copper has been discovered in animal tissues without the use of either paper or charcoal. The above mentioned facts are certainly not without importance to physiology, judicial medicine, and pharmacy, but it is to be hoped, that in following them up, more light will be thrown upon this interesting topic. Fell's Railway over Mont Cents. Dr. H. L. Sellers, of Natchez, Miss., writes us that the form of railway used on Mont Cenis, a notice of which was made in our issue of June 12th, was originally invented by his brother, G. E. Sellers, formerly of Philadelphia, who invented and patented a locomotive, operating exactly like the one in use on the road mentioned, about the year 1885. Our correspondent perhaps feels aggrieved at what seems to him a transferof the honorof thisinventiontoMr. Fell,but we have never understood that the invention was claimed by that gentleman, but, on the contrary, believe it has been understood by him and others who know the history of the matter to be an American invention. "Honor to whom honor is due," is a precept sometimes disregarded by eminent men, but we think in this case no honor has been claimed by Mr. Fell upon the ground of priority or originality in the form of either locomotive or track. He was the first to build and operate a railway on this plan. How to Oat oil Bats. The following is said to be a cheap and effective way to catch rats: Cover a common barrel with stiff, stout paper, tying the edge round the barrel; place a board so that the rats may have easy access to the top ; sprinkle cheese parings or other feed for the rats on the paper for several days, until they begin to think that they have a right to their daily rations from this Source ; then place in the bottom of the barfel a piece of rock about Six or seven inches high, filling with water until only enough of it projects above the water for one rat to lodge upon, Now replace the paper first cutting a cross in the middle, and the first rat that comeS' on the barrel top goes through into the water, and climbs on the rock. The paper comes back to its original position, and the second rat follows the first. Then begins a fight for the possession of the dry place on the stone, the noise of which attracts the others, who share the same fate.