SCIENTIFIC AND USEFUL.

New Zealand Graphic, Volume VIII, Issue 42, 17 October 1891, Page 489

SCIENTIFIC AND USEFUL.

ACROSS AFRICA BY BALLOON. M. Henri Lecomte, the director of the Meteorological School of Aerostation at Paris, proposes to endeavour to cross Africa by balloon, starting from Mozambique. The balloon is to be furnished with a special apparatus for making hydrogen gas during the night time, is to carry provisions for 100 days, and have a capacity of 10,000 cubic metres. Many experienced aeronauts have expressed their opinion that the attempt is a rash one and the aim is quite impracticable. THE BREECH LOADING STEEL RIFLE. The great breech loading steel rifle, the first 12-inch highpower gun was fired for the first time at New York on July 25th. A Board of expert army officers witnessed the test, and pronouncedit a completesuccess. With a reducedcharge of 2501b5. German pi ismatic powder and a projectile weighing 1,0001b5., an initial velocity of 1,473 feet per second was attained, with a pressure of 20,0001b5. to the square inch. The range of the new gun was five miles. Therefore it is fair to presume with an ordinary service charge of 3401b5. a range of twelve miles or more will be reached. THE DEEPEST COAL PITS. The deepest of very deep colliery workings is on the Con tinent of Europe. Ashton Moss colliery, in Lancashire, has a depth of 2,850 ft. below the surface, and the celebrated Monkwearmouth pit in Durham has a depth of I,Booft. In Bohemia there are two shafts which, measured from the surface, have a depth of 3,546 ft. and 3,509 ft. respectively, but the commencement of the sinking is 1,760 ft. above the sea level. In Prussian-Saxony there is a boring which has been carried down to the prodigious depth of 5,736 ft. In Belgium a shaft has been sunk below sea level 3.084 ft, and this is supposed to be the deepest penetration of the earth’s crust yet effected. At these depths the workmen are always perspiring. They have a uniform temperature a trifle too high for comfort. A CURIOUS STORY OF A BULLET. A few months since, whilst cruising in the Bay of Biscay on board the Frederick the Great, a Mr Hans Lohlmann unfortunately was shot by a rifle bullet, which entered his head, making a hole of some considerable extent. He was landed at Gibraltar and sent home, where the best possible medical assistance was obtained. The wound healed, and he was considered to have recovered from the effects of the accident, when a swelling appeared on the opposite side of the head to that where he had been shot. This was opened, and, to the astonishment of the medical gentleman interested, the bullet was discovered, it having passed from one side of the head to the other. It was extracted, and Mr Lohlmann now has it mounted in gold, and wears it on his watch chain. It bears two dates—one that on which it entered ■ his head, and the other when it was extracted. THE PROPOSED EXPEDITION TO THE SOUTH POLE. Another attempt is being made to raise the requited sum of £15,000 to fit out an expedition of geographical and commercial research to the Antarctic regions. Sir Thomas Elder has signified his intention of subscribing £5,000. The hon. secretaries of the Royal Geographical Society of Australasia, South Australian "branch, have received from Baron Sir F. von Mueller information of the following telegram from Stockholm: —‘Swedish Consul just received telegram. Nordfenskjold declares £15,000 amply sufficient; £5,000 are found here (Stockholm). Please inform me if you mean to say that £lO,OOO have been found in Australia.’ Baron Nordenskjold will command the expedition if sufficient funds are forthcoming to meet the expenses. Some £lO,OOO have been guaranteed, leaving now only £5,000 more to complete the required sum, and this amount it is endeavoured to obtain by an appeal. THE ANTS AND THE BAKER. A pretty ant story comes from Chicago. A pastrycook in that city found his shop invaded by a colony of ants, who feasted nightly on the delicacies deposited on a certain shelf. After cudgelling his brains for some time in order to discover a plan for stopping the depredations of the active insects, he resolved to lay a streak of treacle around the tiray containing the coveted food. In due time the ants came forth in their hundreds, and were led towards the feast by their chief. On reaching the line scouts were then sent out to survey, and eventually the ‘ word of command ’ was passed around, and instantly the main body of the ants made for a part of the wall where the plaster had been broken by a nail. Here each snatched up a tiny piece of mortar and returned to the spot indicated, where their burdens were deposited upon the molasses. By this means and after an infinite amount of labour, a bridge was formed and the triumphant army marched forward to partake of the fruits of victory, the baker meanwhile standing by filled with wonder. HOW TIGERS SECURE THEIR PREY. A sudden dash of two hundred yards in the open is nothing uncommon, and the author mentions the case of one tigress, with whom he says he was at one time quite intimately acquainted, who used to catch hog or deer almost daily on a perfectly open and burned-up plain. Small animals are, for the most part, despatched with a blow of the paw ; but in the case of the more bulky, the experienced tiger, leaping on the back of his victim, giips the neck in front of the withers with his jaws, one fore-paw clasping the shoulder of the animal and the other fully extended under the throat. Should he be unable to crush the spine with his jaws, he will then jerk the head back violently and thereby break the neck. An expert says :‘ I have examined hundreds of animals killed by tigers, and have never yet detected injury to the blood-vessels of the throat, but invariably marks attributable to the above mentioned method.’ In removing his prey the tiger frequently displays almost phenomenal strength and activity. In one case cited a young tigress leaped up a perpendicular rock some six feet high with a man weighing nearly eleven stone in her jaws, and on another occasion a male tiger drugged an exceptionally large buffalo up a bank at least ten feet high.