SCIENCE, MECHANICAL INVENTIONS, ETC.

New Zealand Herald, Volume XXXVIII, Issue 11650, 11 May 1901, Page 6 (Supplement)

SCIENCE, MECHANICAL INVENTIONS, ETC.

WHAT SCIENTISTS HAVE TO DISCOVER. The microbes of cancer, scarlet fever, smallpox, and measles have yet to be discovered. Probably the disease that has baffled study and research in the line of bacteriology more than any other is that of cancer. No microbe or parasite has been discovered in that disease, although countless observations have been made. Possibly when this organism is discovered the cure. perhaps in the nature of a serum, will suggest itself, and cancer, after so long withstanding his efforts, will yield to man's persevering research. It is possible, too, that the blood tests now being used in typhoid and malaria may be utilised. There remains much yet to be learned of the maladies of diabetes and Bright's disease, which also rank among the less curable of prevalent affections. The prospects of curing consumption aire exceedingly promising. Improved hygienic conditions, light, air. and exercise will doubtless do much to control tuberculosis and lower the death-rate from that disease — now 10 per cent, of the entire mortality. Among the unsolved problems one should record heart disease, in the treatment of which there is great room for improvement. The heart never stops for repairs, and the difficulty in treating diseases of that organ can be easily appreciated. Insanity is another of the problems. The chances are that the cure of insanity will be greatly helped by a more thorough study of pathological lesions of the brain. This method may explain many morbid conditions which ire still unexplained and open a way for the treatment of the dread disease. The treatment of epidemics is still a problem, but that it has already been partially solved is evidenced by the comparative rareness of widespread pestilence in modern times. THE VALVE of REKRIOKRATION*. Since Professor Linde brought his coldproducir.g plant into commercial use there has been a very great advance in scientific refrigeration, which now comprehends in itself an important industry. A question has recently arisen whether or not the freezing of alimentary substances, which forms the chief purpose of the various forms of refrigerating apparatus in use. is injurious to their qualities as fond for human consumption. It is contended by the refrigerating advocates that the prejudice against frozen meat —ur at least the preference accorded to it in its fresh form, is wholly unjustifiable; and that defrosted-' meat, in every essential that appeals to either the hygienist of the epicure, is quite as good as any other. Sonic elaborate experiments are being devised to afford demonstrative proof of the truth of this rllegation. These are to be undertaken at the expense of some of those interested in the refrigerating industry, and the tests may be expected to prove of an interesting and perhaps grateful nature. Meat of both the "defrosted" and fresh type will be prepared for consumption in the' ordinary manner, and examiners appointed to ascertain by the natural means at their disposal which of the two is superior as pronounced by the organs of mastication and deglutition to the oilier. "Defrosted"' moat has already been submitted to the analyst, who has investigated different samples to discover any undue bacteriological tendency in meat kept for a long time in refrigeration, an ordeal from which it has emerged in triumph. the .V-:\V WTI.sBAi'H LAMP. It will be remembered that what is considered an important, if undeveloped, asset of '.he Welsbach Incandescent Gas Light Company consists of the new electric lamp invented by Dr. Alter, some details of which have already Great expectations have been held of this illuminant. whose introduction to the market, however, still lingers in the rear of anticipation, it being thought it might possibly prove the means of restoring the company to something of its former financial position. If the facts are as stated to the writer, it appears there is likely to be a serious question as to whether the lamp ill ever possess a commercial existence at all. Osmium, the mineral of which the filament of the lamp is composed, is almost the rarest metal in existence. It is a hundred rimes more scarce than platinum, being derived from osmiridium. which itself .3 found in the Ural Mountains, combined with platinum ore to the extent of about one per cent. Its rarity and cost, therefore, would preclude its usage on the large scale presupposed by a public adoption of the lamp; while the metal, which is obtained in the form of a crystalline powder, is most obdurate to manufacturing treatment, so that the difficulties in preparing perfect filaments are enormous. LIQUID AIR. It has been noticed that if liquid air be allowed to evaporate freely, the nitrogen in it pisses away more quickly than the oxygen, and that consequently the final product is a gas very rich in the latter element. A German engineer, named ITempk'. proposes to utilise this property in the combustion of low-class fuels, such as lignite and peat, and has constructed a furnace for the purpose. At a proper distance from the latter the liquid air is allowed to vaporise, and the first vapours, rich in nitrogen and poor in oxygen, are separated, while those coming later, containing as much as 50 per cent, of oxygen, are led under the grate bars, with the result of greatly intensifying the combustion.

THE I'OISO.'sOf:-; EFFECTS OF BICHROMATE OF POTASH. A very real danger is ire—:.; both to photographers who make us- of bichromate of potash and to those engaged in it" preparation unless suite!de pre ions are taken to safeguard themselves against the consequences of to.-;:!'--!, which tire manifested in skin eruptions, ulceration of the nasal mucous membrane, and in some case* ulceration of the throat and tonsils. In trinsforming the neutral eliminate m potash by means of an a'-id into the hii Inornate, the vapour evolved carries with it an infinite number of pulverised part ■'<!••:• of the bichromate: which are diffused throughout the air of the building in which the process is curried on, and if inhaled by tic mouth create a bitter and very disagreeable taste ; profuse salivation results, and the •bichromate is thrown off in the saliva before any permanent injury is caused. If. however, these molecules are inhaled by the nose, they are dissolved in the layer of secretion which lies on the membrane covering the nasal septum and create a violent pricking 'sensation, the eyes are suffuse-! with tears, arid attacks of sneezing are caused. In time, portions of the mucous membrane are detached, and ulceration of the septum of the nose is set up. It was found, at the lime some investigations were made on this subject, that those of the workmen who vvre addicted to the use of snoli' were free front nasal ulceration, while none of the others escaped. — lit nest (,'. Finchnm, M.U.C.N. ling.. L.P..C.P. London, in the Amateur Photographer. TELEPHONE TP.OT'HI.F.s. For many years past it has been recognised that the contact of telephone transmitters and receivers with the ears and lips of a great number of persons might result in the transmission of contagious diseases. The microphonic plate against which we speak is in particular a receptacle for all sorts of organic matter, including drops if saliva, which dry on it, and form a" Hotting dust breeding places for noxious germs. The speaker must articulate distinctly and ophis mouth wide. There is, therefore. • s he inhales and exhales, an opportunity for a free exchange of microbes. All these tacts, which are by no means new to students •■!' hygiene, have at last begun to he ,i;e,,] officially. The Revue Knevclopadique, in tin article by lb. Forettu de Cotirinelles, pioles the following regarding what is being danj in France: "By advice of a. special commission, M. Mougeot has recommended that in public telephone booths the vibrating plates of the transmitters and the cones of the receivers should be wiped with a cloth slightly moistened with dilute carbolic acid, and the walls of the booths In sprayed with the same daily, in Vienna the telephone booths are furnished with napkins beating the inscription, 'Wipe, if you please. These measures, good though they are. will be effective only when the napkin is changed frequently. There is a still better plan— to do away with the present form of telephone apparatus and to substitute new systems in which hearing and speaking are effected at some distance. It is well known that the loud-speaking telephone, capable of being heard at a distance, is an accomplished fact. We have at least, three systems, based either on perfection of line and of instruments, or on a combination of microphone and phonograph."— The Family Doctor.