Science & Progress.

New Zealand Mail, Issue 1152, 30 March 1894, Page 37

Science & Progress.

AT THE PASTEUR INSTITUTE.

Inoculation For Hydrophobia. With "Kxaltcd" nml "Attenuated" Microbes. Thirteen years ago very few people admitted the part, played by bacteria in the fcvorld. and those who did admit their existence were very much at sea what to do about them. Dr. Ronx, assistant to M. Pasteur at the institute in Paris, confesses |he aggravating fact that the microbe of hydrophobia has not yet been found, nevertheless he says, "The inoculation process floes work," and "We have conquered hydrophobia." The operation of inoculating for hydrophobia ris founded on tho theory that if an "'attenuated" microbe —that is, a microbe so treated that his power of doingharmhas been reduced to a low degree—is introduced into a body he will produce an indisposi-

tion which is not itself serious, but which is sufficient to render the body proof against attacks of the original microbe. Now, M. Pasteur has discovered that it Is possible to so treat a microbe that his power of evil is of any degree—that is, to "exalt" as well as to "attenuate" him. Having these microbes of varying strengths, he invented a method of graduated vaccination —that is, by beginning with a virus of low degree and increasing each day the strength of the virus., an operator arrives at a point where he can vaccinate a body with a virus stronger than there is any danger of its ever being exposed to in nature. He thus secures lasting immunity. Thus, in vaccinating against rabies, the patient is treated first with a weak virus; this is followed by one more powerful, and SO on, until at the end a highly "exalted" one is injected safely. It is this treatment which is practiced daily at the Pasteur institute, in the inoculation room where a recent visitor, the author of the foregoing explanation of the theory of the treatment, witnessed the following scene: Gathered in a kind of pen formed by a little fence were three members of the institution —a secretary, whose business it is to keep track of the number of persons to be treated, with each particular virus; an assistant, who has prepared the virus for the day's use; 12 small wineglasses of cloudy liquid protected b\- small paper funnels, and by a table the iuoculator. The roll was called, and a half dozen men entered the room. They were to be inoculated with a virus of the lowest strength, most of them for the first time. They showed a bewildered and comic embarrassment as the attendant directed them to bare the bypogastrium. The embarrassment changed to a momentary look of distress as they felt their arms pinned behind their backs and the sharp needle inject asyringeful of virus into the delicate flesh. The first class of men and boys passed out, and the women and little children entered. They were succeeded by a second class, and so on until all had been treated.

According to the published reports of the institute, 2,071 persons were vaccinated in 1880 against hydrophobia; 25 of them died — .04 of 1 per cent. la ISS7 1.770 persons were treated: 13 died —.73 of 1 per cent. Id ISSS 1,022 were treated; 9 died—.ss of 1 per cent. In 15591,830 were treated; 7 died—.3S of 1 per cent. In IS9O 1,540 were treated; 5 died—. 32 of 1 per cent. In IS9I 1,559 were treated; 3 died—. 19 of 1 per cent. Each, year the percentage of deaths has been lower. In the six years there is an average of just about one-half of 1 per cent of loss.

The Art of Making: Damascus Steel. Aii lowa man is reported by a contemporary as claiming to have discovered the lost art of making Damascus steel atone-half the cost of modern steel. The new product, lie asserts, tempers two points higher than ordinary steel, and within two points of the diamond. It contains no carbon, requires no rolling, the finished product may be molded instead of hammered, and its tempering possesses the quality of springiness. When he shows to the work! a sword blade that bends double, and then springs to its original straight ness, that will cut a feather pillow or a bar of steel or iron, and yet whose analysis shows nothing but "wrought iron, though it is four-fifths as bard as a diamond, he believes the world ■will appreciate the fact that he has discovered Damascus steel. Collecting Electricity From tllio Air. An apparatus for collecting electricity from the air is described bj" a French journal as xi revolving wheel having eight spokes, but no rim. Each spoke is a conductor, insulated from the hub and having a metallic crossarm at its farther end. Two brushes are arranged near the hub, one above and one below the center. These brushes are always in contact with the spokes, pointing vertically upward and vertically downward, respectively, during the revolution, and therefore lead off from them the electric charges collected from the atmosphere a.t the top and at the bottom of the wheel. -