SCIENTIFIC AND USEFUL.

Cromwell Argus, Volume XXV, Issue 1268, 8 August 1893, Page 7

SCIENTIFIC AND USEFUL.

GIABB beioeb Seventeen houses constructed entirely of hollow glass bricks will figure at the Chicago Exhibition, where they will he used as offices, workshops, and stores, A highly decorative effect will be obtained by using bricks of variegated glass, adhering to each other by means of colourless cement, a building of this nature lit from within by electricity presenting a fairy like aspect unapproaohod by structures of sheet-glass and iron, A BIG LUMP OP COAL. An enormous cob of cannel coal has been raised from the Abram Collieries Wigan, and sent for shipment to Boston It is said to be t> e largest block of coal ever dug from tho earth, and weighs over 12 tons. It took nine months to hew it out of the seam, and the cost of obtaining it was JBIOOO, or about .£B3 per ton. From Boston ihe coal will be, conveyed by (rain to Chicago for the World’s Fair. .. AN OLD AND STEONG TUBXLB. The great turtle found in tho Artillery Barracks at Port-Louis, in 1810, when Mauritius was ceded to Great Britain, is, although almost blind, still alive ; it weighs, according to a French observer, 150 kilogrammes, and measures 2*59 metres (8J ft) across the carapace. Its height from the ground to the top of the carapace, when it walks, is about ’6B metres (about 2ft ). It is believed to be 200 years old, at nevertheless it carries two men on its back with ease, SMALL LUMINOUS FOUNTAINS. The success of hj« luminous fountains at the Pans Exhibition of 1889 has suggestion to M. Trouve the idea of producing the effec’s on a small scale and cheaply. Several forms of this small fountain are described in the 'Bulletin de la Society d’ Encouragement.’ Instead of illuminating the water jets by lateral mirro-s, M.Trouve lights up with an incandesce* t lamp at the focus of a parabolic mirror a sort of inverted glass with apertures for tbe liquid. BPFBCTB OP A ‘ COLD ‘WAVE.’ The' cold wave ’ which passed over Hong Kong in January last bad disastrous effects on vegetable and insect life. From a 1 fairly green island ’ Hong Kong was turned by it into ‘ a desert-looking land.’ On tbe hills ma’ y species of plants were killed outright, and in some localities the banana plantations are reported as ruined. Many species of butterflies and other insects had dkappeored , and of others, swarming in the previous spring only a few scattered individuals were to be This refers to the stale of things in tbe laiter half of March, when matters were beginning to improve, HEIGHT OP THE AUBOBA Experiments made at the R >yal Danish Academy have demonstrated approximstely the height of the aurora borealis, M. Adam Paulsen, at Gud-haab, by means of two theodo'itcs s tnated four miles apart, fo>’nd that different aurora displays varied from one to four miles in heig t. Experiments near Capo Farewell showed the height of different auroras to vary from Ito 10 mile?. At Spitzenburg the range of height was from onethird to 18 mi os. In some of Ihe earlier experiments in this direction the observers concluded that the height of tho auroras varied from 90 to 500 miles, A NEW MAGAZINE BIFLE. Some recent trials have beep made with an automatic magazine rifle invented by Messrs Woodgate and Griffith. It is stated that with this gun the whole of the seven cartridges contained in the magazine can be fired within two sec mde, and, allowing ample time for substituting fresh cartridge cases in the magazine, 105 sho's per minute can be fired. At the same time a much greater accuracy of aim th in with other rifles is obtained, owing to the fact that it is not necessary to lower rhe weapo i to reload until the seven cartridges in the Magazine ora exhausted, when the case, being empty, drops out automatically. THE ATTUAOTION OP LIGHT UPON INSECTS. Mr L, Newitt, electrician at tho Elswick Works, in reference to electrical search lights, said in a recent lecture that it might bo interesting to hear what happened during the late war around tho coast of Egypt. Some of the ships had instructions to follow Ihe movements of the enemy by the aid of the search light, which ia every case was more than two miles from the shore. However, in spite of (his great, distance, it was found that millions of winged insects were attracted by this beam of light, and travelled along the beam until they struck the glass in front of the projector and fell into the well around the search light where they accumulate into a mass 2 feet deep. THE KOTA AUBIGJE The origin of the new star which appeared last year in tho constellation Auriga lias been much discussed am mg astronomers. Dr Huggins suggested that it was a dark body which had * become suddenly enwrapt in burning hydrogen ’ —that, in short, it was a world on fire. Mr Monok thought tho supposition of a star rushing through a gaseous nebula would best ocoount for tho phenomena, the star bursting into flame as meteorites do when rushing through the earth’s atmosphere. Mr Maunder’s idea that * a long and d*’nse swarm of meteors rushed through the atmosphere of a star’ is something similar. Mr Lockyor propou> ded the theory that the sudden out-blaze of light was produced by two swarms of meteorites, rushing with great velocity in opposite directions, having come into collision. A writer in Nature examines the different hypotheses, and finds that tbe phenomena, telescopic and spectroscopic, are bestexplained on Mr Lookyer’s theory. Prom latest observatory reports it would seem that the * new star ’ is rapidly assuming the form of a nebula. LONG ExPOSUEE STAB PHOTOGRAPHS. At a meeting of the British Astronomical Association, Dr Gill, of the Cape Observatory, exhibited, among others, a photograph of a portion of the sky taken with 12 hours’ exposure. He stated that if a shilling were held at arm’s length it would cover tbe extent of skv shown on this plate, yet no fewer than 200.000 to 250,000 stars had left distinct marks upon it, hardly one of which was visible to the naked eye. For the benefit of those who were but beginners in astronomy, Dr Gill explained that it was impossible to expose a plate continuously for twelve hours, since the change of position of the earth would be snob that the telescope could not follow a star for that length of time. The particular photograph they had under consideration had been exposed for three hours on four different nights, and there were also breaks in the exposure caused by clouds; still, so rigid were the mountings of the guiding telescope, that it was possible to turn it back after each break, so that the cross wires should bieeot the same guiding star, and it was impossible to trace any signs of movement even in the smallest star. This showed that the whole instrument was as perfect as it could be.