SCIENCE SIFTINGS.

Auckland Star, Volume XXXIX, Issue 129, 30 May 1908, Page 12

SCIENCE SIFTINGS.

DEEP-SEA, DIVING. An. ingenious new diving-bell has lately I been, patented; by a S wabian. inventor. It is claimed that with this apparatus a . descent can be- made into the very depths :of the ocean without danger. The new : device- is constructed off aluminium. BALLOONS TWELVE MILKS HIGH. At a gathering of German scientists, Professor Hergesell recently gave an account of the latest results achieved by means of unmanned balloons. Carrying with them scientific instruments, these balloons have reached heights of from eleven to twelve and a-half miles. And they have registered the record natural temperature of 148deg, below zero Fahrenheit!: Perhaps the most remarkable •fact brought out by these records, however, is that the air is coldest over the equator, and warmer towards the Poles. Thus, the thermometers sent up in the tropics registered the abnormally low reading given above, while those sent up in the latitude of Central Europe only sank to from 76deg. to 58deg. below zero. Theee experiments indicate, moreover, that atmospheric conditions which affect our weather do not occur above seven miles high. GLASS 4000 YEARS OLD. Specimens of glass found in Egyptian tombs have proved to be more than 4000 years old, and glass bottles are represented on tombs >fc least 1500 years earlier. In Mesopotamia the art of making glass has been traced for at least 2000 years B:C. But all the glass of antiquity was of inferior quality and was .almost useless for purposes where the rays of light were to be transmitted unbroken and with undiminished energy. Mirrors were also, made in Egypt thousands of years before the Christian era. iThey gave a very imperfect image, and were not much esteemed. TANTALUM AND STEEL. No sooner has some previously unused metal been found applicable to some branch of industry than many other unexpected uses are discovered for it. This is just now strikingly true of tantalum, originally called into requisition to furnish an improved form of filament for electric lamps. Nicolarflot has found that tantalum, and even its almost inseparable companion, columbium, when added in certain proportions to steel, render the steel very hard, but leave it, at the same time, ductile. THE STRENGTH OF GLASS. Glass is not a substance that we can figure the strength of as we ran a great many other things with which we are familiar. It varies greatly in itself. The strongest glass, as a rule, breaks into the greatest number of fragments, tornparing the strength of thin friars with , thick," the former is relatively the '•stronger; this is a thing very often lost sight of. Tiien. again, as to the difference between roujrh plate and polished plate, we find polished plato the stronger. This is perhaps to be attributed to the fact that all these very fine surface hair cracks are polished out. These only go into the glas.s to a certain depth, air! when they are all or nearly all polished and ground off, there is less chance for ! some of them to form the hasis of a crack, and thereby the gla~s is inrreaseil lin strength. Test.- hnve been made ani l some formulae have been arrived at. A3 'was to be expert'ed. they show very irj regular results as to th? strength of glass.

SMOKING IX THE ORIENT. The conclusion to which careful inquiry ha-s led, writes Prof. Ray Lankester, is that though various Asiatic- races h.ivp appreciated ihe smoke i>l various herbs and enjoyed onhnlinir it from time immemorial, yet them was no definite '■ftmokingf' in earlier iinic?. No pipes or rolled-up packets of dried leaves—to b , ." , placed in the mouth and sucked whilst slowly burning — were in use before the introduction of tobacco by European.-, who brought the tobacco-plant from America and the mode of enjoying its smokp. and passed on its seeds to the people of Turkey, Persia. India, China, and Ja^an. THE DISTANCE OF THE SUN. Camille Flammarion has just published a most interesting little work on astronomy for children, and. in fact, for everybody who wishes to read the science in a plain form. Flammarion says that if the moon were removed to the same distance from the earth as the sun is. then the moon would be invisible. If a railway train travelled to the sun at the uniform rate of thirty-seven and one-half miles an hour it would take 140.000.000 minutes to reach the sun. or 103.472 days, or 283 vea.rs. The cost of a railway ticket for" the sun at the rate of lid per mile would cost £5D(i.000. These prices sink into insignificance when compared with the cost of a railway ticket to the nearest star after the sun, for such a ticket would cost £ 164.000,000.000.

CHEAPER RADIUM i Professor E. Rutherford, the young j Jvew Zealander who started the scientitie world by his new theories on radium, «iid, in a lecture at the Royal Institution recently, that owing to recent discoveries it was hoped that radio-active suhstances ivould soon be on sale in large quantities, and at a comparatively low price. INDIA RUBBER PAVEMENTS. The "Revue Scientifiqiie" contains some interesting particulars concerning the adoption of indiarubber pavements for large cities. If this could he accomplish, ed it would rob town life of many of its terrors, and the roar of traffic which never quite dies out in busy places would become deadened, to the great relief of the citizen. The never-ending rumble over wood and granite pavements is a nerve-wrecking sensation to which generations of town life have not quite accustomed us. It appears that one of the first experiments with indiarubber pavements was made in London as far back as 1881, and though it was conducted on a very small scale it must be described as successful. The rubber stood the hardest wear and tear, and when taken up twenty years afterwards it was still in excellent condition. The initial cost of placing down rubber pavement is heavy, as it is three times as expensive as the best redwood blocks. But the life of a wood pavement is only four against the twenty years of rubber. It will easily be seen, therefore, that rubber is much cheaper in the end. It is Jiardly necessray to add that the material which is used for pavements is not all pure rubber—indeed, it contains only ten to fifteen per cent of that material. A city paved entirely with noise-deadening rubber should be a pleasant place to dwell in, and the delights of motoring and cycling over level streets and roads laid with indiarubber would be too glorioua for. words.