216 Lord Bayleigh [March 16, 



WEEKLY EVENING MEETING, 



Friday, March 16, 1894. 



The Right Hon. Earl Percy, F.S.A. Vice-President, 

 in the Chair. 



The Eight Hon. Lord Eayleigh, M.A. D.C.L. LL.D. F.R.S. M.B.I. 



PROFESSOR OF NATURAL PHILOSOPHY, R.I. 



The Scientific Work of Tyndall. 



It is fitting that the present season should not pass without a refer- 

 ence on these evenings to the work of him whose tragic death a few 

 months since was felt as a personal grief and loss by every member 

 of the Eoyal Institution. With much diffidence I have undertaken the 

 task to-night, wishing that it had fallen to one better qualified by long 

 and intimate acquaintance to do justice to the theme. For Tyndall 

 was a personality of exceeding interest. He exercised an often magical 

 charm upon those with whom he was closely associated, but when his 

 opposition was aroused he showed himself a keen controversialist. 

 My subject of to-night is but half the story. 



Even the strictest devotion of the time at my disposal to a survey 

 of the scientific work of Tyndall will not allow of more than a very 

 imperfect and fragmentary treatment. During his thirty years of 

 labour within these walls he ranged over a vast field, and accumulated 

 results of a very varied character, important not only to the culti- 

 vators of the physical sciences, but also to the biologist. All that I 

 can hope to do is to bring back to your recollection the more salient 

 points of his work, and to illustrate them where possible by experi- 

 ments of his own devising. 



In looking through the catalogue of scientific papers issued by 

 the Eoyal Society, one of the first entries under the name of Tyndall 

 relates to a matter comparatively simple, but still of some interest. 

 It has been noticed that when a jet of liquid is allowed to play into a 

 receiving vessel, a good deal of air is sometimes carried down with it, 

 while at other times this does not happen. The matter was examined 

 experimentally by Tyndall, and he found that it was closely connected 

 with the peculiar transformation undergone by a jet of liquid which 

 had been previously investigated by Savart. A jet as it issues from 

 the nozzle is at first cylindrical, but after a time it becomes what 

 the physiologists call varicose ; it swells in some places and contracts 

 in others. This effect becomes more exaggerated as the jet descends, 

 until the swellings separate into distinct drops, which follow one 

 another in single file. Savart showed that under the influence of 



