CHAP, iv.] THE CRUISES OF THE 'PORCUPINE: 



191 



ture, there being no further diminution to the bottom. 

 This serial sounding and all the subsequent tempera- 

 ture observations taken during the Mediterranean 

 cruise showed that the trough of the Mediterranean 

 from the depth of 100 fathoms downwards is filled 

 with a mass of water at almost exactly the same 

 temperature throughout, a temperature a little above 

 or below 12'75 C. 



The following instances have been cited by Dr. 

 Carpenter from the earlier observations in the Medi- 

 terranean basin, to show the great uniformity of the 

 bottom temperature for all depths : 



At this last Station (No. 47) a serial sounding was 

 taken, which entirely confirmed the results of the 

 first (No. 40) : 



Surface . 20 9 C. 



10 fathoms . 15 2 



20 



30 



40 



50 



100 



845 



14 -4 

 13 8 

 13' 3 

 13 1 

 12 -6 

 12 6 



