SCIENTIFIC AND USEFUL.

New Zealand Graphic, Volume VIII, Issue 48, 28 November 1891, Page 627

SCIENTIFIC AND USEFUL.

ABOUT CANCER. Dr. Bayard Holmes presents some interesting conclusions in regard to cancer. He says that the disease is the work of a parasite and it is • a close messmate of man.' It attacks only those who have passed the reproductive peiiod. INVISIBLE LIFE. Notwithstanding the assertion that there is no animal life in Death Valley, California, U.S.A., the American government surveying party has found two hundred varieties of mammals and sixty varieties of reptiles, specimens of which have been forwarded to Washington. VENTILATING RAILWAY C ARRIAGES. A new method of ventilating railroad carriages and preventing dust from entering with the air has appeared in France. The more quickly the train moves the more rapidly the apparatus works. The air is made to traverse a receptacle containing water, which cools it and relieves it of dust, after which it goes through another filtering before entering the carriage. THE COMING ALUMINIUM AGE. The age of aluminium is slowly creeping upon us. At least the metal is becoming cheaper, and a boat ten feet by five constructed of it has just been launched in Germany, propelled by a naphtha motor. More ductile and light by far than steel, and possessed of vastly greater tensile strength, it only remains for the discovery ot more ready methods in extracting this metal, which is omnipresent in the earth's crust, to revolutionize industry again. USE OF 01.11 SHOES. The old boots and shoes which, when quite past wealing by anyone, find their way into old dustbins, are extremely valuable, and find their way into our houses in most artistic forms. They are soaked in many waters to remove the dirt, all nails and threads are picked out, and the leather reduced to a thick pulp, from which is made the now fashionable wall paper, screens, etc. Bookbinders and frame makers also know full well the value of this pulp, and carriage builders press it into sheets, which are invaluable for the roofs of the most luxurious vehicles. ELECTRICITY FROM WATER-POWER. There has been frequent reference to the utilization of water-power to electricity in Switzerland, but the great activity in this line of work there demands further note. During the past year it is said that no less than eighty projects for utilizing water power were being carried out. One scheme is to obtain 10,000 horse power fiom the Rhine at Rhinefelden, and the capital already subscribed is £650,000. At Soluthurn a company has been formed to make a canal between the Emma and the Aar to utilize the power thus obtained. A Zurich concern will erect woollen mills to employ 600 workmen, the power to be used being electricity. A SUBJECT OF CONTROVERSY. That a man can feel pain in an amputated limb is still a subject of controversy; A physician who believes it says : —‘ Many of the nerves that furnish communication between the brain are not injured in their activity by the amputation of their lo.wer portion, and convey sensation as readily as ever. The brain fails to recognise the fact that the function of the nerve has changed, and that the part in which it formerly terminated exists no longer. Therefore, when a sensation is felt conveyed by a nerve that in the unmaimed body led to the foot, the feeling is the same as if the foot were still in place. If certain nerves in an amputated leg be touched the feeling is exactly the same as if the foot were touched, and the sensation of pain is felt not where it is applied, but where the mind has been in the habit of receiv iug communications from the nerve in question.’ PHOTOGRAPHS OF THE MOON. Objects upon the moon, says a contemporary, are detected by their shadows, and a projection or eminence fifty feet high casts a shadow large enough to be seen through the Lick telescope. If Professor Holden, studying his series of photographs, should discover some day a new shadow where none had been cast before when the moon was at the same position and under the same light, he would Know that something had been erected under the surface, either a part of the crust upheaved by some internal movement or a building put up by living creatures. The shape of the shadows might tell the name of the projection. It the moon were inhabited, it is very likely the works of man would have been seen before now ; the growing and harvesting of crops would produce changes of appeal ance easily distinguishable by the aid of such a glass as the Lick telescope. The moon appears to be a desolate waste of played out volcanoes and cooled-off lava beds, without atmosphere. ARTIFICIAL KAIN. The Optician, commenting upon the fact that the United States Government has voted £l,BOO for the purpose of experiments in the artificial production of rain, says :—lf argument is wanted to prove the fallacy of the precious gunpowder theory, and to conclusively prove the perspiration theory of abnormal rainfalls, a fairly reliable substantiation will be found as follows According to Professor Huxley, one soldier may be expected to give off in battle half a gallon of water by the skin and lungs. Now, twelve hours is a fair estimate for the average time of conflict in battle. This gives six gallons of water per man during twelve hours, which, by further calculation, we find will cover twelve square feet three quarter-inch deep. This is as plain as day, and if the United States Government hopes to succeed in its meteorological efforts, it had better turn its attention to the sweat of the brow and discard the villainous saltpetre and its congeners.