OCEAN GARDENS ; 



In the distribution of the rocks, I would always 

 allow at least one point to project above the water, 

 in order to afford the opportunity to those animals 

 whose instincts lead them to seek occasional expo- 

 sure to the air, the means of gratifying it by that 

 contrivance. I have thought, indeed, of construct- 

 ing a kind of double Aquarium, and perfecting a 

 contrivance by means of which a large portion of 

 water should flow gradually from one tank to the 

 other at fixed periods, in imitation of the ebb and 

 flow of the tide. Many interesting phenomena 

 would be exhibited in this manner, such as the 

 closing of the Actinice as the water receded, and 

 their expansion as it covered them on its return. 

 This alternation, too, might be found highly advan- 

 tageous to the health and development of the 

 animals whose natural habitat lies between high 

 and low water-mark, and whose constitution is 

 therefore framed to require entire or partial expo- 

 sure to the air at certain intervals of time. I also 

 prefer, as preserving a similar set of analogies, a 

 sloping bottom, similar to that of the coast. Por 

 instance, if the slate back of the Aquarium be 

 placed next the light, which is its proper position, 

 as the light ought to penetrate the water entirely 

 through its upper or horizontal surface, then I 



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