506 president's address. 



Globigerinffi, &c. The water at these great depths must be either 

 perfectly still or the motion must be of the gentlest kind. The 

 prevalence of light at even the greatest depths seems to be settled 

 by the fact that colour is not wanting, and that the eyes of On- 

 copus, for example, are remarkably large, and more highly or- 

 ganized than those of fishes. Dr. Carpenter incHnes to the 

 opinion that there is no difference in size between the animals 

 that Hve in shallow water and those that dwell in the greatest 

 depths. 



One question of singular interest is, on what food do these 

 various living organisms exist '? It would seem that plant life 

 is confined to a comparatively short distance from the shore, 

 and to that well-known floating Sargasso weed, the existence 

 of which in great masses so troubled the companions of Co- 

 lumbus. 



An American expedition of a like character has also been at 

 work. They did not succeed in dredging fr'om so great a depth 

 as in the case of the "Porcupine," not more than eight hundred 

 and twenty fathoms ever having been attained by them. But 

 the discovery of corals at great depths will probably tend to 

 modify not a little the opinions held of late years as to the for- 

 mation of coral reefs and islands. 



Another subject on which some interesting light has been 

 thi'own is the depth of the great Pacific Ocean. A careful com- 

 parison of the times at which the great earthquake wave of 

 August, 1868, which devastated so large a part of South America, 

 reached the distant shores of Japan, New Zealand, the Sandwich 

 Islands, and other places, with Aiiy's weU-known theory of the 

 velocity and breadth of sea waves, has led to an astonishing cor- 

 respondence between the fact and the theoiy. The gi'eatest 

 mean depth would seem to be between Aiica and the Sandwich 

 Islands — two thousand five hundred and sixty-five fathoms. 



But if this past year has been fr'iiitful in unveOing the secrets 

 of the ocean, not less so has it been in reading to us some of the 

 deeper mysteries of the skies. The wonderful and most inter- 

 esting discoveries, made by the aid of the spectroscope, as to 

 the nature of the body of the sun, the composition of the nebulae, 



