100 
Proceedings of the Royal Society 
£ = 0, not only at the boundaries, but throughout the space for 
which the approximate equation (22) is sufficiently nearly true. 
And, putting for l 2 its value above, we have 
which agrees with (16) above. 
I hope in a future communication to the Eoyal Society to go in 
detail into particular cases, and to give details of the solutions at 
present indicated, some of which present great interest in relation 
to tidal theory, and also in relation to the abstract theory of vortex 
motion. The characteristic differences between cases in which o- is 
greater than 2<o, or less than 2w, are remarkably interesting, and of 
great importance in respect to the theory of diurnal tides in the 
Mediterranean, or other more or less nearly closed seas in middle 
latitudes, and of the lunar fortnightly tide of the whole ocean. 
It is to he remarked that the preceding theory is applicable to 
waves or vibrations in any narrow lake or portion of the sea 
covering not more than a few degrees of the earth’s surface, if 
for w we take the component of the earth’s angular velocity round 
a vertical through the locality, that is to say, co = y sin Z, where y 
denotes the earth’s angular velocity, and l the latitude. 
2. On the Effects of Chloroform, Ethidene Dichloride, and 
Ether on Blood - Pressure. By Joseph Coats, M.D., 
William Ramsay, Ph.D., and John G. M'Kendrick, M.D., 
the University of Glasgow. Communicated by Professor 
M‘Kendrick. 
Dr Coats stated that this communication referred to part of an 
investigation on the physiological action of anaesthetics, undertaken, 
at the request of the British Medical Association, by Dr Ramsay, 
Dr M‘Kendrick, and himself. After describing the method of 
obtaining accurate tracings of variations in blood-pressure by means 
of a kymograph, he stated that the facts obtained from these re- 
whence 
~gv 9 
Abstract. 
