SCIENCE NOTES.

Otago Witness, Issue 2299, 24 March 1898, Page 54

SCIENCE NOTES.

■ . ■ There can be no doubt that there is a tendency at the present day to administer arsscic in many diseases, especially those of a neurotic character, in which formerly it was never employed, and to exhibit that drag in large doses not previously used. ] Practitioners who prescribe that drug in i these heroic doses will do well to study, the report of a case narrated at a recent meeting of the Clinical Society by Dr ColmaD. A ' girl Buffering from chorea took arsenic in ■ doses of 15 minims, given three times a day , . for 31 days, except on six of those days, when it was discontinued, as she had gastric disturbance. The chorea was speedily cured, i and the drug stopped ; but 13 days after its ' cessation she began to suffer from symptoms ■ which ushered in peripheral neuritis and ! almost complete paralysis of all extensor | muscles below the knees, with well-marked i reaction of degeneration, and some weakness , I of the extensor mnscles of the forearms. She had arsenical pigmentation of the neck and the groins ; but under treatment by rest, ; massage', and electricity, she rapidly recovered. The case well illustrated the serious risk attending this method of treatment ; and that the untoward symptoms were not due to any special idiosyncrasy of thepatient was shown by the fact, that Dr .Colman had seen at least two other serious cases of the kind, whilst Dr Beevor had also met with a case in an adult, and there are others on record. — British Medical Jour c a?. j • . • The authorities controlling the elec- : trie lighting plant at Geneva are starting a ; calcium carbide works in order to utilise the idle hours of their plant. The dynamos are driven by water power, of which there is an abundance. Special attention is being paid to the use of good material and the production of the best results. The coke contains ! but 5 per cent, of ash. The lime is very . , pure, containing 99 to 99 5 per cent, of i calcium oxide. Each furnace will take 500- j horse power (6000 amperes afc 57 volts), j They are probably the largest used for the 1 manufacture of calcium carbide. The fur- j 5 nace is a large cylindrical crucible 59 in in ] diameter and 32in higb. Tbe electrode is f made of compressed carbon in six pieces, | each 60in long, 5 2in by 9 2in in section. I The weight of tbe six carbons is over 8581b, t\ and the total section is 287 square inches. I In order to reduce labour '6iiarge3 as much ; as possible, tbe pulverising of the coke, mix- < ing the lime and carbon, and other opera- ] tions are peformed mechanically. From the time the crude material is received until it comes from the furnace but one man's labour , is required, most of the operations being » automatic. 1 • . • The last castinga by Edison's magnetic I ore-separating process, it was found, could ! not be broken by 151b sledges in the hands of a strong man. Twenty-five pound sledges equally failed. This waa so remarkable that Mr Edison chemically analysed the specimens, and discovered either a new element or a' new combination of elements, which point to the possibility of reproducing iron castings at will with the best characteristics of wrought metal, and surpassing malleable iron both in respect to cheapness and rapidity of production. * . • A German chemist, says Merck's Re- j port (U.S ), has prepared a fluid that, has the | | power, when injected into tbe tissue of a plant near its roots, of arsethetisiDg the plant. The plant does not die. but stops growing, maintaining its fresh, green appearance, though its vitality is apparently suspended. It .is also independent of the changes in temperature, the most delicate i hothouse plants continuing to bloom in the open. The composition of the fluid is shrouded in the greatest secrecy, tout it is 6aid to have a pungent odour and to b8 colourless. ■ . • Lord Kelvin showed in a racsnt address that all tbe oxygen in the atmosphere ; probably c«me from the action of sunlight j on plants. When the earth was a globe of j hot liquid it contained no vegetable fuel, j and probably no free oxygen. But as it j cooled off plants appeared on it» surface, j and these began to evolve oxygen through the medium of the sunbeams Upon the oxygen thus derived we depend upon the maintenance of life by breathing. we barn coal or other vegetable fuerWprae up oxygen, and ifc is to plants again that we j owe the restoration of tbe oxygen thus lost j to the air. If they failed to keep' up a sufficient supply, the atmosphere would gra- i dually part with its oxygen, and the inhabi- i tants of the .earth would gradually disappear in consequence of asphyxiation. A VEILED ORB. By a Banker. Twice a year necessarily, and occasionally \ as often as five times a year, the great centre j

of the solar system is temporarily hidden i from our view, either wholly or partially, i both its light and heat being for the time ! withdrawn. Although from a scientific ' point of view a total eclipse of the sun ia I of far greater interest than either a partial or an annular eclipse, yet to the tfaked eye the latter is much more interesting than either the total or partial variety. Annular eclipses occur very seldom, the last occurrence (which the writer had the good fortuna to witness) having taken i place in the year 1847. On the 18ch j July of tho present year this phe- j nomenon again recurs, but will be visible ] only in the region comprising tha eastern j portion of Polynesia. For a few minutes { j during the middle of the eclipse the specI tacle is startlingly beautiful ; a brilliant fiery I ring of perfect symmetry, about the width ' of the crescent of a m,oon a few hours old, i shines forth suspended in the darkened I heavens, presenting a marvellously weird and j strange aspect, even more impressive than when the obscuration ie complete. A full solar eclipse is very rarely visible in England, the last occasion having been in 1715. Us predecessor having occurred in a.d. 1140 (Milner) ; and there will ba no recurrence or the phenomenon until February 3, 191(5. The spectacle of a total eclipse, as j seen through a large astronomical telescope, | i 8 described as being a vision of wondrous beauty. The luminary itself ie, of course, entirely hidden from view, but from behind the intervening dark body of the moon great rose-coloured protuberances, 50,000 miles or more in length, are proj«cted, others equally brilliant being tinted a greenish-blue or a bright red ; some rising erec. from the disc, others, agitated and torn, deflected at right i angles, while great tongues of flaming hydro- ■ gen, more than half a million miles in length, rush forth from the solar disc, blazing with impetuous vehemence and in varying power. The whole stirring pageant impresses the observer with a realisation of the tremendous j inherent energy existing in the sun, which > for probably millions of years has continued to burn in this fiery and violSnt manner, with an intensity and fervency s"b vigorous j and mighty that ths heat of tha huge and ' stupendous furnace is imparted to the whole ' planetary gvstem ; this earth, though more than. 90 millions of miles distant, receiving the solar heat in burning strength and neverdiminishing energy. The question as to the ' means whereby the fuel is supplied to the , s«n to produce this gigantic and e^er-blazing cobflagration remains an unsolvabla mystery. The generally- received opinion is that the great orb by its enormous power of attrac- • tion draws vast quantifies of meteoric stones and matter to irself, thus providing a con- j stant -source of energy; it is difficult, how-"! ever, understand how this can be, for in J that case this earth would continually intercept large quantities of these bodies in the course of her revolutions. This does not appear to be the case, as the "shooting stars " appear to be a ring of meteorites possessing as fixed an orbit as that of the earth itself. On the other hand, it is unintelligible how the tremendous combnstiou perpstually going on can be continued indefinitely without a replenishment of some kind or other. But an eclipse which took place rearly 19 j centuries ago was of infinitely greater inte- ; rest and import than any ol! theee phenomena we have been coueidering. For then. He, who is the Light of the World, and whose dazzling glory illumines the heaven of heavens, and who is the Creator of the Universes, allowed that glory and majesty to be temporarily eclipsed and veiled, in order that by suffering in our stead ami re- j ceiving the punishment duo to us as our substitute, those who choose to accept the benefit thus conferred may, when they are transferred to the spirit world, ba received into that glorious sphere where all io bright ecstasy and joyous rapture. But there are others, who refuse or neglect to do so, whose pitiable lot will be cast in a dismal horror of darkness and galling remorse 1