Advancing science : being personal reminiscences of the British Association in the nineteenth century / by Sir Oliver Lodge.

  • Lodge, Oliver, Sir, 1851-1940.
Date:
1931
Catalogue details

Licence: In copyright

Credit: Advancing science : being personal reminiscences of the British Association in the nineteenth century / by Sir Oliver Lodge. Source: Wellcome Collection.

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    the course of experiments, we electrified the rod to see what effect that would have on the dust-free coat. I he method used was to have a long rod or thick wire, projecting straight into a cigar-box with glazed sides, illuminated laterally by a strong light (in those days lime rendered incandescent by an oxyhydrogen jet), and looked at longitudinally through a microscope.’ 1 he temperature was regulated by applications of heat to the portion of the rod outside the box, and the box was filled with smoke. On now electrifying the rod gently, the dust-free coat seen round it thickened, contorted itself, and ultimately extended all through the box. In fact, we found that anything like a brush discharge cleared a confined space of smoke or dust completely. The particles first congealed into flakes and then clung to the sides of the box. We began trying that, on what we thought was a large scale,using a bell-jar with a pointed rod passing into it, and connected with one terminal of a Voss machine. The smoke used in the cigar-box had been tobacco smoke, blown into it by the inde¬ fatigable smoker J. W. Clark. For the larger experi¬ ment we used the smoke of burning magnesium, which is clean and easy to produce ; but we used also ammo¬ nium chloride or sulphide, produced by generating ammonia and either distilling hydrochloric acid or burning sulphur into the same space. We also cleared a cellar of turpentine smoke, looking at it from outside, thereby making a horrid mess ; but we usually em-