112 PRINCIPLE OF AQUARIUM. 



sudden invasion of Tadpoles, " Tittlebats," and Sea- Anemones ; 

 and Aquarium-keeping became the order of the day. 



The chemical principles involved in this ingenious and beautiful 

 contrivance are now too well known to require any lengthened ex- 

 planation. It is a matter of familiar knowledge, that in the process 

 of respiration, animals consume the oxygen or life- sustaining prin- 

 ciple of the atmosphere, and give back in return a quantity of 

 carbonic-acid gas, which is as deleterious to animal life as the 

 oxygen is healthful and invigorating. It thus happens that 

 when animals are confined by themselves in a limited quantity 

 of air, this double process of deterioration speedily renders the 

 fluid absolutely poisonous and destructive of life. But in 

 respect to plants, a precisely opposite state of things obtains. 

 By a process somewhat analogous to the respiration of animals, 

 though not to be confounded with it, the vegetable world is 

 continually appropriating the carbonic acid of the atmosphere, 

 and giving back oxygen. In their relation to the atmosphere, 

 therefore, the two great divisions of the organic world beautifully 

 balance one another each taking and appropriating to its own 

 use what would be injurious to the other, and each giving back 

 that which the necessities of the other require. 



In respect to the free atmosphere this mutually counteractive 

 influence of the animal and vegetable kingdoms has long been 

 familiar ; we owe the Aquarium to the discovery that it 

 equally holds good with respect to the atmospheric air contained 

 in water. 



The gentleman to whom the world is mainly indebted for this 

 discovery, and for its practical application to natural history 

 purposes, is Mr. Warington, of Apothecaries' Hall, who may 

 fairly claim to be the originator of the Aquarium. 



But about the same time that Mr. Warington was engaged in 

 his experiments, Mr. Gosse was busily carrying on a similar 

 series, and with the same object in view ; and though not quite 

 so successful as Mr. Warington at first, he was so far satisfied 

 of the practicability of the Aquarium as to suggest the establish- 

 ment of a series of them in the Zoological Gardens, Regent's 

 Park. The suggestion was readily adopted, and early in the 

 summer of 1853 the " Fish House," which for more than twelve 

 months previously had been in preparation, was opened to the 

 public. The success of the novel exhibition was extraordinary. 



