THE EXTENT OF MODERN COMMERCE. 771 



museums of Europe, large aquariums have been built, and an 

 opportunity thus afforded for the study of the various animal 

 forms, the habits of the vegetable growths, and their relations. 

 Some of these structures are so arranged that they surround a 

 ioom which receives its light only through the water in the 

 aquaria, and thus the spectator, without disturbing the fish, 

 can watch them feeding and performing all their actions. 



From this arrangement of the aquaria, as the light passes 

 from the water to the eye, the spectator is not distubed in his 

 vision, as he is by trying to look into the water from above, 

 by the refraction of the light. A great deal that has been 

 learned in modern times concerning the growth of the vegeta- 

 tion of the sea, of the habits of the animals, of their manner of 

 life, their food and their growth, has been obtained from the 

 chance of observation afforded by the various aquaria. Beside 

 me positive benefits which have thus resulted from the public 

 aquaria, those in smaller form afford for the lover of natural 

 history a new and interesting way of carrying on his studies, 

 [n this way also the habits of observation are formed in the 

 young, and it is fair to believe that the spirit of inquiry thus 

 excited will tend to increase the knowledge of the phenomena 

 of life, and its relations to the conditions of existence. 



It has been by this course that the race itself has risen from 

 barbarism to its present degree of civilization, and with the 

 new appliances of modern times, it is evidently impossible to 

 limit the probabilities of advance in the future. 



A few facts about the extent of our commerce will show the 

 difference of the spirit with which the ocean is regarded in 

 modern times, compared with that prevailing in anti- 

 quity ; and the different use we have learned to make of it, from 

 the time when the exchanges of the world were confined to a 

 p ew coasters, who hardly ventured out of the sight of land, 

 fo give even the most condensed summary of the world's 

 commerce to-day would require a series of volumes ; but a 



