164 PHYSICAL INVESTIGATIONS. 



51 and 53, and tlie surface and bottom samples for eacli station 

 showing no marked differences. The highest values are found for 

 samples taken down Channel and on the southern side, a decrease 

 being observed in Start Bay and along the coast to the eastwards. 



At a depth of 10 fathoms a distribution of temperature is found 

 which remains practically unaltered at all stations until the bottom 

 is reached ; even in the case of station VII the temperature at 73 

 fathoms is only 0'2° F. lower than that at 10 fathoms. At these 

 depths the highest temperatures are found off the English coast 

 east of the Bill of Portland, and again in the neighbourhood of the 

 Channel Islands, colder water occurring in mid- Channel at stations 

 II, Ila, and III, and VII and VIII, and between Start Point and the 

 Bill of Portland, where the minimum of 50'6° F. is reached, the 

 isothermals curving into Start Bay and turning south again. 



On the surface the distribution of temperature is peculiar ; and 

 although the observations here are very much more numerous, less 

 weight can be attached to their results on account of the action of wind. 

 It is to be noted that on the first day of the cruise the wind was south- 

 westerly, light, freshening, and veering a little towards evening, till 

 at 2 a.m. next morning it was blowing hard from about west. After 

 daybreak the force greatly diminished, and the wind gradually veered 

 to north-west and died away altogether. On the third day the wind 

 was westerly and extremely light, dying away to a calm at times. 



Wherever undisturbed by land influences, the line between 

 stations I and IV may be said to show a uniform temperature at 

 the surface of 53*7° F. Further up Channel, i. e. between stations 

 VI, VII, VIII, and IX, a lower temperature is found, varying irre- 

 gularly at the time of observation between 52° F. and 53° F. ; and 

 this colder surface water seems to extend at any rate round the 

 island of Guernsey. In the area covered by stations IX, X, XI, and 

 XII a temperature between 53° F. and 54° F. is found, rising as 

 we approach Poole Bay to about 55° F. 



In the region between Start Point and the Bill of Portland a 

 totally different distribution occurs. We find here the highest tempe- 

 ratures of the whole cruise, rising suddenly 2° as the Bill of Portland 

 is passed, and slowly increasing thereafter till the maximum of 67° F. 

 is reached off Beer Head. A sudden drop to below 52° is observed 

 over the Skerries off Dartmouth Harbour. Soundings XIII and 

 XIV show that the layer of warmer water is quite superficial, the 

 temperature falling to 51-9° F. at 6 fathoms in XIII, and to 50-9° F. 

 at 8 fathoms in XIV. It may be noted that extra samples, No. 42 

 and No. 45, show no change in the density at 15*56°. With regard 

 to column 14, densities in situ, we have of course simply the results 

 of the distribution of temperature, with the small variations of 



