SCIENTIFIC.

Otago Witness, Issue 1852, 20 May 1887, Page 35

SCIENTIFIC.

i The recent destruction of the beautiful Pink a,nd White Terraces of New Zealand has given rise to a discussion as tq the rtit'e at which the silicate „which formed, them,.' wasdeposibed. One observer states that the pencil marks and dates, writtep after thp manner of tourists in certain parts of the terraces, became coated with such a. thin " layer of the flinty material even in the course of 25 years, that the words and figures written looked as if freshly done. Mr Lant ' Carpenter, .on' the other hand,. -records thefact that the wir.g of a bird, shdfc as it was flying over the terraces, became so com.pletely covered with, the ,flinfcy material m course of a fortnight that its form could - not be recognised. Doubtless, both statements are true," and that while the nameswere, written in % spot at which, the silicate Jag.' deposited ; sWly,xthe, wing of the bird >ppened i; to-*fau in" a place more favourably tuated. The same kind of discussion has i often arisen concerning the deposit of stalagr mite in the various bone-caves, with a view of settling the date of some of the bones and other things buried beneath. Calculations Lbafsedftibpn sijfch date, njus"|ob^io|sly be open to* nnicb) chance' of 'error*— Chambers' JJourr r nal. t\ /v> ', • t . ; ,,,. 1} / I ' i f ) f , , '< Opiate years, fhe popular impression and* 'the- scientific- statements ,as 'to'^he' influence of the amount of' oxygen in the~airoritf!es blood f 'ha?e b.een:jnr.,cpnfiipik..'';Tbe generpf belief is that an increase i» tfe« proportion "

of oxygen in the air would accelerate the vital actions, exhilarate for a time, and then produce consequent exhaustion, and this is borne out by the accounts given of the behaviour of small animals in an atmosphere of pure oxygen — they become very excited for a little, but soon die of exhaustion. On the other hand, scientific experiments on the blood, when removed from the body, have proved that its power of absorbing oxygen from' an 1 atmosphere remains pretty much the same no matter how rich or how poor, within certain limits, the atmosphere may be in oxygen. In order to decide between the two opinions Kempner has made three independent researches on the power of tha blood, in the living body to absorb oxygen, and has found that when the amount of oxygen in the air is increased from its ordinary proportion of 20 per cent, up to 30 per ent. no difference in the amount absorbed in the lungs can be detected, while on the ther hand, if the amount of oxygen in the ir falls even a few per cent, below the normal, a diminished absorbtion can at once be detected. Natures air supply is of the right strength'; it cannot be strengthened with advantage nor weakened without disadvantage. The editor of the Medical Press and Circular takes .quite a utilitarian view of the presence of microbes in animal and vegetable economy. Speaking in a somewhat acetious way, he writes as follows:— "A great deal of ill-feeling has been excited anent these unfortunate animalculae, whose size should have insured them protection against contumely and insult. There is scarcely a disease, scarcely a mishap, but what they are inveighed against and condemned without a hearing, and very often, indeed, without being even called upon to put in an appearance. As an independent journal we feel it our duty to protest against wholesale and often unfounded denunciations by individuals not unfrequently formulated more with a view to self-aggrandisement and notoriety than from any positive ill-will towards these humble little beast. We will not deny that a few of them have gone astray. When they engage in the elaboration of the virus of typhoid, smallpox, and measles, to say nothing of hydrophobia, and a variety of other uncomfortable visi ! ations for mankind, it is only natural that we should retaliate by calling the opprobrious names in dog Latin, and by poisoning them wholesale when and where we can bring our animosity to bear upon them. They have manifestly violated the statutes in such cases made and provided. But on the other hand, he will assert, with the courage and independance that is our wont, that if there were no microbes there would be no mankind, and our disputes would be silenced in death. Our very digestion depends uporf them to a great extent, and if they were withdrawn from circulation we should very shortly become painfully aware of the fact. They are accused of contaminating our water, but it is equally certain that were it not for their ceaseless activity all the water in the world would be a concentrated solution of extrementitious and noxious products, the disintegration of which is due to these little organisms. The importance of microbes to the growth of plants has been practically demonstrated by M. Laurent, who obtained only one-fourth as much buckwheat from sterilised mould as in Boil containing bacteria. As an American contemporary points out, there are about 1000 species busily engaged in the destructions of wood, and, were it not for their invention", all the trees that ever grew would be standing to day, living, or it may be dead, but in any case as solid, as sound, and as firm as when they ceased to grow, and all life must have been choked out ages since. Fire alone would have relieved mother earth of the incubus thus weighing upon her, but only with the result of leaving every patch of land a parched and ash-covered area, inadequate—at any rate, for some time— to the maintenance of life, even if we ourselves had not at the same time been prematurely scorched off the face of the earth. No ; let there be no class distinctions; every community has its black sheep, and these should very properly be branded with the mark of infamy. The existence, however, of these misconducted atoms will not justify our extending the anathemas to the countless millions of their species in whom and with whom we live, and move and have our being.

Manufacturers of kerosene oil say that all lamps are safe with good oil, and that the quality of oil can be ascertained by the following test: — Take a pint cup, fill it nearly full o£ water warmed so that an ordinary thermometer immersed in it will show 120deg, pour a small quantity of oil on the water, stir it a little, then pass a lighted match quickly but closely over the surface of the oil once ; if "it ignites, the oil is unsafe. If purchases are made of from 3gal to sgal at a time and this test is made, people can protect themselves.

Children starving to death on account ol their inability to digest food, will find a most marvelous food and remedy in Scott's Kmulsion of Pure Cod Livrh Oil with Hypophosphites Very palatable and easily digested. Read the following testimonial: "I have prescribed • Scott's Emulsion ' in cases of children suffering from wasting aud mal-nutrition, and can report moat, fay urably of its good effect ; it has been in each, case baken most readily.

W. Perkins, M.R.0.8.,

Medical Supt., Burleigh Hospital, Eng. Large and small bottles at all Chemists, 4s |6d and 2s 6ii.— [Advt.] '