868 NATURAL SCIENCE [June 



The Deift of the Channel 



The paper of most interest in the last number of the Journal of the 

 Marine Biological Association of the United Kingdom, issued at the 

 end of April, is a " Eeport on the Surface Drift of the English 

 Channel and Neighbouring Seas during 1897," by Mr W. Garstang. 

 It will be remembered that about a year ago the Director of the 

 Plymouth Laboratory instituted an investigation by means of soda- 

 water bottles, which were cast upon the waters, and which, we are 

 glad to say, were in a large number of cases returned to him after 

 many days. The locality where each bottle started upon its journey 

 was accurately recorded, as well as the date on which it started. 

 By means of a numbered post-card enclosed in the bottle, informa- 

 tion as to the place reached by it, with some indication of the date, 

 was returned to Mr Allen. The whole Report is of remarkable 

 interest, but we must confine ourselves here to quoting the conclu- 

 sions in Mr Garstang's own words : — 



" Enough has been said, I think, to show that the method 

 employed here for tracing the actual influence of the winds on the 

 water is sufficiently accurate for practical purposes, and that by its 

 employment, with proper precautions, the influence of the winds 

 may be separated from that of other factors which operate in the 

 production of surface currents. From this point of view the method 

 may be of considerable use in the future for determining the exist- 

 ence of currents not produced by local wind-action. At the same 

 time the method requires to be tested extensively before it can be 

 used as a basis for conclusions. The present report pretends only 

 to show that the relation between wind-action and surface currents 

 is capable of quantitative study, and that the results obtained by 

 the use of the methods here described are sufficiently accurate to 

 encourage the further use of them. This we are doing during the 

 present year on a larger scale, and the results will be set out in next 

 year's report. It is very desirable that experiments should be 

 made to determine the depth of the currents induced by wind-action, 

 and we propose to attempt this work during the present year. A 

 comparison of results obtained by bottles floating at the surface, and 

 by other objects designed to come under the influence of lower strata 

 of water, should yield results of considerable value. Until such 

 experiments are made, however, it does not appear to be desirable 

 to say too much upon the practical aspects of the experiments 

 described in this report. We have obtained a general view of the 

 movements of the uppermost layer of water, and we may be certain 

 that similar, though slower, movements also affect the layers im- 

 mediately subjacent ; but the actual depth to which this movement 

 would be communicated under different conditions of wind and tide 



