248 Mr. J. Croll on the e Challenger' $' Crucial Test of the 



North Pacific Ocean. — I have just had an opportunity of 

 reading Dr. Carpenter's interesting " Summary of Recent Ob- 

 servations on the Temperature of the North Pacific made in the 

 U.S.S. ' Tuscarora'"*. The temperature-soundings made in 

 that vessel seem to me to show that the thermal condition of 

 the North Pacific is just as irreconcilable with the gravitation 

 theory as that of the North Atlantic. They show that the 

 North Pacific is much colder than the North Atlantic, and that 

 the immense stratum of warm water found in the latter is wanting 

 in the North Pacific. But as the North Pacific is almost entirely 

 cut off from the cold Arctic basin, its waters, according to the 

 gravitation theory, instead of being colder, ought to be much 

 warmer than those of the Atlantic. 



But this is not all; these soundings bring to light the 

 remarkable fact, as will be seen from the subjoined Table, that 

 the North Pacific is actually warmer at latitude 52° than at 

 latitude 43°. 





I. 



II. 



III. 



IV. 



V. 



Depth, 



Lat. 43° 21' N. 



Lat. 46° N. 



Lat. 48° 40' N. 



Lat. 51° 39' N. 



Lat. 52° 14' N. 



in 

 fathoms. 



Long.l49°12'E. 



Long. 150° 45'E. 



Long. 156° 7' E. 



Long. 164° 30'E. 



Long. 173° 14' E. 



Temperature. 



Temperature. 



Temperature. 



Temperature. 



Temperature. 





o 





o 





o 



Surface. 



430 



371 



41-9 



450 



45-9 



30 



33-6 





32 1 



34-8 



41 5 



50 



33-3 



339 



32-5 



341 



39-2 



100 



33-3 



32-9 



322 



35-3 



38-3 



200 





32-9 



326 



34-6 





300 



332 







34-6 





500 



33-6 







34-7 



371 



Now it is obvious that down to 500 fathoms (the depth to 

 which these observations extend), for columns of equal weight, 

 column V. (in lat. 52°) must be higher than column I. (in lat. 43°). 

 It therefore follows, from the principles of hydrostatics, that 

 unless the condition of things be totally the reverse below 500 

 fathoms, which is not at all likely, the top of column V. must 

 stand at a higher level than that of column I.; and consequently 

 if there be any surface-flow due to gravitation, it must be towards 

 the equator, and not towards the pole. 



Dr. Carpenter himself seems aware of the difficulties besetting 

 the theory. But it appears to me that the explanation which 

 he offers is as hostile to the theory as are the facts themselves 

 to be explained. His explanation of the abnormally low tem- 



* Proceedings of the Royal Geographical Society, vol. xix. No. 7, 1875. 



