CAMPAIGN AGAINST CANCER

New Zealand Herald, Volume LXII, Issue 19150, 16 October 1925, Page 15

CAMPAIGN AGAINST CANCER

MARVELS OF PHOTOGRAPHY. LECTURE BY MR. J. H. BARNARD. JniOil OCR OWN COKKESPONJDENT. ] LONDON, Sept. 3. Sir. J. H. Barnard, who has been associated with Dr. Gys in cancer research, was one of the lecturers at the British .Association Conference. Ho gave a very interesting discourse on filter-passing Tixnses. Filter-passing viruses, Mr. Barnard Said, 'svere extremely small bodies. They >~era so small that they would pass through any known porcelain filter, or membrane impervious to any ordinary inediiu.iL It was unsatisfactory that at present there was no method of standardising filters, but work in that direction was now in progress. During the last Jew months work had been done which enabled them to see bodies less than onethird of the size they had previously been sHe to see by the best microscope available. He hoped that the work on which they were now engaged would make it possible to prepare a cinema film which .would show the life-cycle of those small Organisms. Already, Mr. Barnard said, they were sble to photograph viruses magnified 3000 diameters in one-tenth of a second, and to make a series of such photographs in rapid succession. Later he hoped they ."wcmld be able to photograph bodies equivalent to ona fivo-hundredth-thousandth of an inch. At present they could photograph down to one two-hundred-and-fifty-thousandth of an inch. Even now it would .ho possible to prepare a cinema film of extremely small organisms, such as the anthrax bacilli, one hundred-thousandth of an inch in diameter. One probable development in the near future was the uso of a microscope, working in a vacuum, and details of such an instrument were now being worked nut by the National Institute of Medical Research. This would enable them to work with rays smaller even than the ultra-violet rays. Mr. Barnard demonstrated what could he observed with the new microscopy in photographing hundreds of divisions in one tiny speck of powder from a gnat's head and the hairs on the tongue of a blowfly. " Within the last few months," he continued, " we have endeavoured to Improve microscopical methods, so that we could see down to a certain order or size, and that has brought us down to rather less than one-third of the smallest we have been able to see in the best piicroscopes hitherto available." A fascinating description of the method by which the cancer germ was kept and fed in colonies was given by the lecturer. "Wo grew these micro-organisms on a thin film on quarts slides," he explained. " Nutrient agar —a kind of jelly known to microscopists—was spread out in a perfectly even layer on a quartz slide. When this is examined very intensely under the light of a microscope is it seen that the agar is really a spongy material with a number of channels running through it containing fluid. '* We discovered the virus would grow much better on the banks of these running streams. The wonder of this was almost appalir.g. Here were continents in a tube under observation by some mighty giant, with cations living by the sides of brimming rivers. This discovery was so helpful to us that we introduced the method by which we supplied the virus with this fluid material, and we only attempted to photograph these colonies when they were hanging over the edge of the crevasses of the agar and were being fed by the fluid. At "last came the photograph of the cancer germ itself. "We believe, Mr. Barnard declared, " that wo are really showing you that filterable virus which is actually associated with malignant tumour growths of human beings."