SCIENCE NOTES.

Otago Witness, Issue 2604, 10 February 1904, Page 64

SCIENCE NOTES.

— The electric poet invention by which letters and parcels are to be carried at 250 miles an hour, is shortly • (says the St. James'fi Gatette) to be" put to a practical test. A syndicate has been formed to take over the patents from Count Piscicelli, the inventor, and to develop the system. If rthe inventor's claims are established in the forthcoming test, which is to take place outside Rome, it is not too much to cay the postal service will be entirely revolutionised. In effect, the new system aims at (providing by automatio means for all the requirements to which postal correspondence is eubjeot from the moment it is put in the fetter box to the time of its arrival at the offices from which the postman receives it for delivery to its ultimate destination, and at no greater cost than at present. A continuous despatch will be possible from town to town, and from district to district, and so completely will space be annihilated that a letter posted in London will be in Manchester in less than an hour, and in Glasgow in under two hours. The system in appearance will resemble nothing go much as a form of -electric railway. Wires will be carried from place to place on high poles, and on these lines- the boxes which are to faarry the letters and the parcels will run. '.The carriers, which will be made of aluminium, will be fitted with small motors, and equipped with wheels which will grip the ■wires as securely as if they were fastened to them. In addition to supporting the wires, ■the poles can be used as collecting boxes, and by an ingenious arrangement the letters as they drop into the receptacle are marked with the date and the hour, and the stamps are obliterated somewhat in the &ame way as is done at the post offico ; At stated intervals the receptacle is automatioally drawn up to the height of the wires, where it deposits its contents into the carrier which sees that every pole does its duty before it returns to the central office. — A German scientist, G. Thileniue, has recently brought out some interesting conclusions- in regard to the pigmy race, of which some specimens are etill to be met ■with in the central part of Africa. It is probable that the pigmy races have existed also in Europe, at least in some parts of it. 'Phis conclusion is arrived at from the -examination of numerous skeletons which have been found in the region of Brcslau in Silesia. These skeletons are in a rather bad condition, but it is possible to form a good idea of the height of the individuals which must have existed afc least one thousand years ago. Their height is considerably below the ordinary average, being about 4-ft 9in, which represents the mean figure for a ■vrhol& group oi skeletons. Similar remains Lave been found in other parts of Europe not far from the above region ; thus Gillman, of Bale, describes tho remains of pigmies which have been found in Switzerland. In ihis case the average height reaches as low as 4ft 6in. Gutmann has also described the pigmy remains which wore found in Lower Alsace, near Colmar. These are still emaller, and the height of many of the specimens is but 4ft. The pigmy race must be considered as composed of well-formed specimens, and not in any way degenerate or pathologic. They seem to have persisted in Europe until a comparatively recent epoch. The pigmies of Silesia appear to have been the contemporaries of the Romans and slave races, and to have existed until the year 1000 a.d. At present no specimens are to be found in Europe, and it is oly in the central region of Africa that the pigmies are still to be seen. — In the report of tho last Coal Commision, says the Engineering Magazine, the •onclusion is arrived at that at a depth of 3000ffc the temperature of the earth would amount to 98deg Fahr., but it was considered that a depth of at least 4000 ft might ultimately be reached in coal mining. The rate jf increase, the commissioners thought, might for ordinary cases be assumed to be Id&g Fahr. for every 60ft, but it is in reality impossible to give any fixed rate of increase. The report of the- British temperatures during the last 30 years_ tends to show, not only that the temperature gradient varies considerably in different localities, but that it ie not easy to deduce a fixed law of increase applicable to all cases. In some parts of Western America the heat at 3000 ft is almost unbearable, while at the Caluimet md! Hecla, Copper Mine in North Michigan, U.S.A., there is a rise of only 4deg Fahr. in a depth :>f 4400 ft, although no artificial ventilation is resorted to. The temperature of the coal on discovery at the Rosebridge Colliery, in Lancashire, was stated by the management to be 93deg Fahr., but it afterwards fell to 63deg Fahr.

— The often far-reaching significance of tpparently trifling facts was illustrated (says

the London Sun) when Professor Williamson, of Owenis College, Manchester, received from a correspondent a pillbox ''filled with impalpable dust," pe-rfeotly dry, and apparently lifeless. It showed no life under th© microscope in its dry state, but when a little of the dust was added to a few drops of distilled water, chemically pure and free from germs of all kinds, each drop of water soon developed into a world teeming with inhabitants. The particles of the dust, so fin© as to be distinguishable only under a strong microscope, were each a living creature^ — a rotifer — the little animal which is as familiar to microscopiets as the domestic animals are to those who make thoir observations of Nature only with the naked eyo. The rotifer, which has a habit of collecting on housetops, in gutters, and wherever elso ■there is a chance for dust to fall, gels his name from the curious habit he has of beginning to wheel in rapid circles through the water as soon as he is placed in it. "In a couple of minutes," says Profesi-or Williamson, in telling if the conduct of the dust in his pillbox, after he had placed a little of it in water, "tho particles began to move, and in a few minutes more the water abounded with fully-grown and unmistakably hungry specimens of the wheel animalculse. In that brief period, their dried-up tissues imbibed moisture, swelled out to their normal size, and every organ of their bodies was seen actively performing their functions.'"

— Recent despatches have suggested the probability that work upon the Simplon Tunnel in th© Alps would be abandoned booaue© the hot springs encountered made the heat so great that it could not be born©. The difficulties, however, have been solved. I'or a distanoe of six and a-quai-ter miles the mountain, has been penetrated on the north, and for four and a-half miles on trie south side, leaving one and a-haif miles to complete it. A juncture will be effected in May or June, with a maximum of error in the direction of 7in oi Bin. Owing to the great height of the mountains above the tunnel, the presaure ie great, and the temperature of the rocks and springs is correspondingly high. The greatest heat encountered was 133deg Fahr. It is now 126. This temperature, with water falling upon th© workmen, would injure them, but this heat has been reduced by diluting the air with cold from hydraulic mains. To cool the air, a laige volume of fresh air, the temperature of which has bean reduced by means of a high pressure water spray, is sent up to the working face of the tunnel, where it is perfectly cool and fresh in contrast with th© foulness and oppressiv&ncuis usual in other tunnels. There is no sickness among the workmen. There has not been a single case of miners' phthisis, although. 3ooo men have been working for five years.

— Andrews (Chicago Medical Recorder) mentions tho usefulness of the tuning-fork in the diagnosis of fractures, especially of the long bones. The test is made by placing the boll of a stethoscope over the- bone near th© supposed fracture, where the soft tissues are as thin as possible-, and the handle, of a tuning-fork as close to the bone as possible beyond the supposed seat of fracturo. The sound will be transmitted through tho shaft of the bon& to the stethoscope, and through the stethoscope to tho e-aiv of the examiner. When the bone is intact, if rho test is properly mad-e, the sound of the fork will be heard with great distinctness ; but if there is a lack of continuity, the sound will either not be heard at all, or will bo heard very faintly. By comparing the intensity of the sound on the suspected side* with the sound heard undor similar conditions on the normal side, the qucetion of continuity of bone can be determined. The test for fractures is based upon the fact that bone k an excellent conductor of sound waves, while -the soft tiis-sue of th© body conducts sound wav-es very poorly. Th© bell of the stethoscope should fit tightly to the skin, and when comparing the sound and injured -faides, tho instrument should be placed in th© same relative positions. The sound waves will be transmitted through a fracture if the two ends are crowded together ; aleo through a joint, especially if the articular surfaces are forcod together. — Frederick Sedgewick, formerly of Elgin, 111., is the inventor of a cypher code typewriting machine by which it is po=3ibl© to put a communication in cypher which will defy solution except by com© one supplied with th© proper facilities for doing so. This device wae offered for patent some time ago, when it was at one© opposed by George C. Blickensderfer, who claimed that it was an infringement on th© patent which he already held. The usual time- allowed to make out a oa a c in such instances expired without any further effort on th© part of Mr Blickensderfer, and in all probability the patent will be granted. An ordinary me=cage transcribed by this machine, which has a keyboard m many respects the same as a typewriter, issues forth a jumbled mass of letters, buc tho usual methods of tin ravelling a cypher message are defied. Thk is accomplished by an automatic de\ice which changes the relationship of the keyboard and letters at irregular intervals. In this way no one character is in use more than another, and no clue what&\ er i a given for anyone receiving the message surreptitiously to decipher it, and the only way in which this can bo done is by copying the message m aiiOiC-or machine which has been adjusted to correspond with the one on which tho original message was written.

— Statisticians estimate that a period of ?.D months will cover the average widowhood of women under 35.

The special Gabdeh Fertiliser made up by Nimmo and Blair will be found to give es> cellent results when used for Flowers and Vegetables; also for Pot Plants, in and out of greenhouse. 2t is put up i:i 71b bags, at Is 6d each. Ask your storekeeper for it.