ON THE EFFECTS OF OCEANIC CUKRENTS UPON CLIMATES. 451 



tion, an influence is exercised inimical to the development of the lowest 

 infusoria. Twenty-four hours usually sufliced to cause the shaded flasks 

 to pass from clearness to turbidity, while thrice this time left the exposed 

 ones without sensible damage to their transparency. 



This result is not due to mere differences of temperature between the 

 infusions. On many occasions the temperature of the exposed flasks was 

 far more favourable to the development of life than that of the shaded 

 ones. The energy which, in the cases here referred to, prevented putre- 

 faction was energy in the radiant form. 



In no case have I found the flasks sterilized by insolation ; for on 

 removing the exposed ones from the open air to a warm kitchen they 

 infalliby changed from clearness to turbidity. Four and twenty hours 

 were in most cases suSicient to produce this change. 



Life is therefore prevented from developing itself in the infusions, as 

 long as they are exposed to the solar light ; and the paralysis, tlaus 

 produced, enables them to pass through the night-time without alteration. 

 It is, however, a suspension, not a destruction of the germinal power, 

 for, as before stated, when placed in a warm room life was invariably 

 developed. 



Had I had the requisite materials I should have determined, by means 

 of coloured media, or otherwise, the particular constituents of the solar 

 radiation which are concerned in this result. The rays, moreover, which 

 thus interfere with life, must be absorbed by the liquid, or by its germinal 

 matter. It would, therefore, be interesting to ascertain whether, after 

 transmission through a layer of any infusion, the radiation still possessed 

 the power of arresting the development of life in the same infusion. It 

 would also be interesting to examine how far insolation may be employed 

 in the preservation of meat from putrefaction. 



Note. — I would not be understood to say that it is impossible to 

 sterilize an infusion by insolation, but merely to indicate that I have thus 

 far noticed no case of the kind. 



On the Effects of Oceanic Currents upon Climates. 

 By the Kev. Samuel Haughton, 31. D., F.R.S. 



[A communication ordered by the General Committee to be printed in cxtenso 



among the Reports.] 



The Gulf Stream and its counter-current, the Labrador current, produce 

 important effects upon climate, which I propose to investigate in some 

 detail, as much misappi'ehension exists as to what they do and do not do ; 

 and I propose further to consider what the effect of similar currents and 

 counter-cnrrents would be, if admitted to the Arctic Ocean from the 

 Pacific through a widened and deepened Behring Sti'ait, and if admitted 

 to the Arctic Ocean, from the Indian Ocean and Arabian Sea (by lower- 

 ing Mesopotamia), through the Great Caspian depression in the west of 

 Asia.' 



' Mr. Alfred Eussel Wallace has ingeniously proposed these two additional Gulf 

 Streams as causes of climatal changes in recent Geological times in the Arctic Zone, 

 but he does not seem to be aware of the effects of the counter-currents they would 

 necessarily produce. 



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