THE BOOK OF THE AQUARIUM. 
THE FRESH WATER TANK. 
CHAPTER I. 
WHAT IS AN AQUARIUM? 
The Name.—The term vivarium was first applied to 
the vessel containing a collection of specimens of aquatic 
life, and the first vivarium of such a kind, on anything 
like an extensive scale, was that opened to public exhi- 
bition in the Regent’s Park Zoological Gardens. Many 
naturalists had previously made experiments to ascertain 
some certain method of preserving aquatic animals in a 
living and healthy state; and the vivarium, which is the 
result of those experiments, may be considered as an 
imitation of the means employed by nature herself in the 
preservation and perpetuation of the various forms of 
animal and vegetable life which people the oceans and the 
streams. fn 
The vivarium is, therefore, no recent or sudden dis- 
covery, but a growth of years; and its present perfection 
is the fruit of many patient investigations, trials, disap- 
pointments, and determinations to achieve success. 
The term vivarium applies to any collection of animals, 
to a park of deer, a rabbit warren, a menagerie, or even 
