SCIENTIFIC.

Otago Witness, Issue 1893, 2 March 1888, Page 36

SCIENTIFIC.

—An apparatus termed the "aerophore" has been brought out in America for moistening the air of mills and factories, which, as is well known, becomes electrified by the friction of the machinery. In cloth mills the fabric is sometimes inconvenienty electrified. Moistening the air prevents this annoyance. The apparatus consists of a piece of pipe about 20in in diameter, fitted with a circle of fine jets, which discharge the water against a series of studs, which break it into spray. Air is also drawn in, and mingling with the spray, disperses it throughout the apartment. The apparatus, it is stated, can also be utilised for cooling or disinfecting large rooms. — The evolution of chaos into earth, air, fire, and water can be represented in the following manner: In a narrow phial or glass tube, pour mercury to the height of one-fourth of its capacity; for the next fourth, add a saturated solution of subcarbonate of potash; next fourth, methylated or pure spirits of wine, tinted blue ; and lastly, turpentine tinted red. On shaking this mixture together, you will have arepresenta« tion of chaos; but soon, on resting, the elements will . separate themselves, and the mercury will represent earth, the blue spirit air, the red turpentine fire, and the colourless potash solution water. — " Where the untrained eye will see nothing but mire and dirt," says Sir John Lubbock, "science will often reveal exquisite possibilities. The mud we tread under our feet in the street is a grimy mixture of clay and sand, soot and water. Separate the sand, however, as Ruskin observes— let the atoms arrange themselves in peace according to their nature— and you have the opal. Separate the clay and it becomes a white earth, fit for the finest porcelain ; or if it still further purifies itself you have a sapphire. Take the soot, and, if properly treated, it will give you a diamond. While, lastly, the water, purified and distilled, will become a dewdrop or crystallise into a lovely star. Or, again, you may see in a shallow pool either the mud lying at the bottom or the image of the sky above." —The success of the bicycle and tricycle driven by human -leg power has called forth a number of light carriages driven by a mechanical source of energy. Electricity stored in secondary batteries has been the favourite device, but so far the steam carriage appears to have been the most successful. In its latest form petroleum is the fuel used ; it is stored in a small tank under the seat, and can be fed into the fire without the driver soiling his fingers. Petroleum, enough to last a day can be Btored in the tank, but only a two hours' supply of water. However, as 16 miles can be done in an hour ifc is not much of a hardship to have to take in water every 32 miles. It takes a quarter of an hour to get up steam. This is the real difficulty with steam as against stored electricity. —A method of extracting clay from deep pits by means of pumping has recently been introduced on alarge scale in Kent, England. In one case the pipe line from the claybank to the works is ever 1£ mile. The pipe used is Gin in diameter, and the pressure at the pumps is equal to 7501b to the square inch. In order to keep the pipes free from clogging, clean water is always pumped through the column for about 20 minutes after closing work. The moment the pumps are stopped, a foot valve at the lower end of the columm is opened, and the whole pipe is washed clean and emptied. It is claimed that this system of clay extraction is much cheaper than the ordinary way of digging and hoisting in buckets or cars. The clay is mixed with the water by hydraulicking, and all stones and most of the grit are left in the pit. *' —On aome parts of the coast of Sumatra and the neighbouring islands the fishermen test the depth of the sea, and also the nature of the sea bottom, by the noises they hear on applying the ear to one end of an oar of which the other end is plunged in the water. At a depth of 20ft and less the sound is a crepitation, similar to that produced when salt is thrown on burning charcoal ; at 50ft it is like the ticking of a watch, the tic tac being more or less rapid, according to whether the bottom is entirely of coral or alternately of coral and mud, or of sand. If the bottom is entirely of sand the sound is clear; if of mud it resembles the humming of a swarm of bees. On dark nights the fishermen select their fishery grounds according to these indications.

— The recent fatal accident in a lead mine through the ignition of gas by shot firing once more calls attention to the necessity of finding some safer means of blasting rock than is afforded by gunpowder. The offer of Mr Ellis Lever to place in the hands of the Home Secretary the sum of £1000, to be divided between the inventor of «uch a boon and the producer of the best safety lamp for miners' use has, for apparently very inadequate reasons, been rejected by the Government. It would seem, however, from recent experiments, that the new explosive, roburite, described recently by us, fulfils all the conditions required. It will do the same amount of work in detaching rock as gunpowder will, while it emits neither flash nor SDarks. Experiments made in chambers charged with explosive gases mingled with coal-dust showed that roburite does not ignite them. We trust that these results will be verified by further trials, and that by these means one of the most deadly risks which the miner has to meet with will cease to exist.

—A Mean Trick.— Friend : "Well, Eliza, how do you like your husband?" Eliza : " He is a villain." " All men are ; but what has he done ? " " You know he was a widower. Well, I've found out that all his love letters to me were copied verbatim from the ones he wrote to his first wife before he married her." "I shouldn't mind that. He will never send you any more."

Children starving to death on account of their inability to digest food, will find a most marvelous food and remedy in Scott's Emulsion of Purb Cod Liver Oil with Hypophosphites. Very palatable and easily digested. Read the following teslimonial : "I have prescribed ' Soott's Emui.sion ' in cases of children suffering from wasting and mal-nutrition, and can report most favouoably of its good effect; it has been in each case taken most readily. W. Perkins, M.E.0.5., Medical Supf.., Burleigh Hospital, Eng. Large and small bottles at all Chemists, 4s |6d and 2s 6a.— [Advt.]