CHAP. U.J TEE CRUISE OF THE 'LIGHTNING: 79 



were upon the whole as satisfactory as we had yentured 

 to anticipate. The vessel was certainly not well suited 

 for the purpose, and the weather throughout the cruise 

 was very severe. During the six weeks which elapsed 

 between our departure from Oban and our return only 

 ten days were available for dredging in the open sea, 

 and on four of these only we were in water over 500 

 fathoms deep. On our return Dr. Carpenter submitted 

 to the Royal Society a preliminary report on the 

 general results of the cruise, and these were regarded 

 by the Council of the Society as sufficiently new and 

 valuable to justify a strong representation to the 

 Admiralty urging the importance of continuing an 

 investigation which had already, even under unfavour- 

 able circumstances, achieved a fair measure of success. 



It had been shown beyond question that animal 

 life is varied and abundant, represented by all the 

 invertebrate groups, at depths in the ocean down to 

 650 fathoms at least, notwithstanding the extra- 

 ordinary conditions to which animals are there 

 exposed. 



It had been determined that, instead of the water 

 of the sea beyond a certain depth varying according 

 to latitude having a uniform temperature of 4° C, an 

 indraught of Arctic water may have at any depth 

 beyond the influence of the direct rays of the sun a 

 temperature so low as — 2° C. ; or on the other hand, 

 a warm current may have at any moderate depth a 

 temperature of 6°-5 C. : and it had been shown that 

 great masses of water at different temperatures are 

 moving about, each in its particular course ; main- 

 taining a remarkable system of oceanic circulation, 

 and yet keeping so distinct from one another that 



