194 Mr. C. Tomlinson 



Article III. 



Experiments and Observations on Visible Vibration. 

 By Charles Tomlinson, Esq. 



{Continued from vol. ii. p. 133.) 



76. In three papers already published in the Records of 

 General Science during the last year, I detailed, as far as 

 my observations had then extended, several phenomena 

 arising from the vibration of mercury and other fluids con- 

 tained in glass vessels ; and, in continuing the investiga- 

 tion, I have again availed myself of the co-operation and 

 assistance of my friend Mr. Dodd, whose correct musical 

 ear and love of science have rendered the inquiry delight- 

 ful to both of us. 



It will be recollected, that the surface of the mercury, 

 when under the influence of vibration, was described as 

 being rippled by undulae, which assumed such an arrange- 

 ment as to produce a highly pleasing figure or series of 

 figures. (8) 



77. Since the publication of the former papers, I have 

 frequently recurred to this particular part of the subject, 

 with the view of ascertaining whether the figures produced 

 were, in all cases, similar to each other, or whether they 

 were changed or modified by the size of the containing 

 vessel, the bulk of mercury, or the extent of mercurial 

 surface in relation to the bulk ; and, although we have not, 

 as yet, succeeded in eliminating any general law on the 

 subject, we have ascertained, that various figures can be 

 procured from the mercurial surface which are modified, 

 and, in some cases, totally changed, according as one or 

 more of the conditions, just stated, are observed ; and, 

 above all, according to the number of vibrations per second 

 to which the mercury is subjected. We have, therefore, 

 thought the subject, even in its present incomplete state, of 

 sufficient interest to allow us to convey an idea of the nature 

 of these figures, as it is obvious, that in proportion as we 

 become acquainted, by the disturbance at the surface of the 

 mercury, with the impulses which the fluid receives from 

 the glass, so shall we obtain clearer ideas of the reciprocal 

 action of the fluid and the glass when vibrating, and of the 

 nodal divisions of the latter. 





