Science Notes.

New Zealand Mail, Issue 999, 24 April 1891, Page 6

Science Notes.

Electric elevators are the latest. A machine has recently been invented for making shoestrings out of paper. A petroleum motor tricycle has been invented that will rnn forty-miles on one gallon of oil. One of the recent applications of eleotrioity""that promises to bo of considerable benefit to sea going men is a log for registering the rate of travel of high-speed vessels.

Yachtsmen who do not like the black tar in their deck seams can now get it white, a white pitch having been invented that can be -fhn into the seams hot, and which will then stand the sun’s heat in any climate.

The Germans seem to be the world in making discoveries in medicine. Somual is the name of a new hypnotio re. oently discovered by a Berlin physician. Its effects are less depressing than those of ehloral.

The Royal Railroad Commission at Berlin is testing electric lights for railroad use. It has had two experimental cars equipped with incandesoent lamps, storage batteries beneath the cars supplying the current.

A scheme has been adopted for the removal of sand deposited on the railroad tracks near the Upper Columbia river by the frequent sandstorms by sluicing it into the river by means of water supplied by a force, pump on the river.

It !b said that there is an element in the common pineapple similar to pepsine, and of such remarkable strength that the juice of a single apple will digest ten pounds of beef. It is further stated that the juice of the fruit ia a very active solvent of the membrane fonnd in diphtheria.

An alarm for telling when a ship reaches a predetermined depth of water is now being tried aboard her Majesty’s ship Rambler in the Red Sea. It consists of a wire sounding* apparatus, having a sinker, which, on coming in contact with the bottom, relieves the drum on board ship and sounds a bell.

Fire-proof construction of buildings is slowly growing more aod more of an exact science. A species of porous terra-cotta filling is rapidly coming into nse. Sixty thousand dollars’ worth of it was recently put into one building in New York. Experts say, however, that as f*r as fire-proof floors are concerned alternate layers of .plank and cement form the most impenetrable of constructions.

Systems for distributing power in cities from a central station are coming more into age every day." Steam, electricity and compressed air ore the common agents, but Paris has a system which is the reverse of that employing compressed air. The motors operate by a vacuum created by immense air pumps at the central station. The cost per horse-power per hour is 23 cents, about the same as with ordinary gas engine when illuminating gas is used.

A silver mine .in Colorado is about to he worked by electricity. The mine is at the top of a mountain about 2000 feet high, and the carrying up of coal has hitherto been a very serious item of expense. It is the intention of the miniog company to utilize a waterfall at the foot of the mountain, where an electric plant to generate 100-horse, power wilt be placed. The power will be transmitted thence to the motors at the summit of the mountain, and the mining operations will be conduoted wholly by electricity.

This is a novel application of the idea_ of execution by electricity, by means of whioh it is designed to put a speedy end to_ rodents and all manner of noxious crawling and flying creatures. This electric trap forms the subject of an Amerioan patent recently issued to Mr F. Soherer, a resident of Paris, France. And suitable lure or bait is located within a cage, behind a grid composed of metal rods or wires, arranged side by side to form the positive and negative wires of the circuit. When the rat or other foredoomed victim, seeking the bait, conics in contact with the wires of the grid, the circuit is thereby closed. Of ccuise, the current must be strong enough to produce a fatal shock, or the invention would not succeed as an electric trap.

The shell of the crab and lobster owes its bluish grey colour to the superposition of two pigments or colouring matters, which have been isolated—a red pigment and a blue. one. As long as these two pigments exist simultaneously, the crustaceans remain grey. But the blue pigment is very fugitive, and sometimes, under the influence of a disease, it is destroyed, and crabs are found with portions of their shell more or less reddish. When the crustaceans are immersed in boiling water, the bine pigment is entirely destroyed, and the red pigment which is very stable, appears alone iu all its brilliancy.

Some interesting experiments have been made with gyrostats in the French Navy. One of these has been mounted on the Turenne for the purpose of adjusting the compasses of the ship. The method adopted depends on the fact that the plane of rotation is very high, and hence, by swinging the ship, the indication of the compass can be compared with those of the gyrostat, and corrected accordingly. A small gyrostat has also been fitted up to the sextant, ana thus an invariable line of sigut obtained, independent of the motion of the ship, when the instrument is set rotating. The device is said to have proved very useful in making observations in rough weather aod at night time.