Volume 1
The life of William Thomson, Baron Kelvin of Largs / by Silvanus P. Thompson.
- Silvanus P. Thompson
- Date:
- 1910
Licence: Public Domain Mark
Credit: The life of William Thomson, Baron Kelvin of Largs / by Silvanus P. Thompson. Source: Wellcome Collection.
561/626 page 527
![~My wife has been feeling much better and able to walk more since she came here, and it seems as if she has derived real benefit from the waters. It is very kind of you to propose coming here to see us, and I am sorry you are engaged these next two Sundays, as I am afraid we shall have left before the 12th. All my spare time is now spent on “ Wirbelbewegung,” and there will be a great deal to say on that and other matters which I must keep till we meet. My wife joins me in kind regards, and I remain, yours always truly, WILLIAM THOMSON. The business which Thomson alludes to was in connection with the French Atlantic Cable, from Brest to St. Pierre, which was then projected, and of which he was one of the consulting electricians. The Company was floated at the end of August. On his return to Scotland he wrote :— LARGS, BY GREENOCK, Se, 3, 1868. My DEAR HELMHOLTZ—I had intended to write to you regarding your paper on a discontinuity of fluid motion, and suggest that friction at the place of rapid motion or tendency to rapid motion close to the edge may, rather than avoidance of negative pressure, be the determining cause of the slipping. Consider instead of a perfect edge an infinitely thin plate (which does not exist in nature) or tube of finite thickness with a regularly rounded lip. If the slipping which you investigate de- pends on avoidance of negative pressure, it should com- mence at A or A’ [at edge or bottom of the lip], according to lesser or greater pressure in the undisturbed fluid. But would it beso? I suspect that if the experiment were tried in a liquid under greater or less pressure, little or no difference would be found in the locality where slipping commences. Is it not possible that the real cause of the formation of a vortex-sheet may be viscosity which exists in every real liquid, and that the ideal case of a perfect](https://iiif.wellcomecollection.org/image/b31360403_0001_0561.jp2/full/800%2C/0/default.jpg)
