120 SEA- WATER AQUARIA. 



it should be stored in great dark reservoirs, and should be circulated^ 

 but 7iot changed. ... It is true that if a marine aquarium were to 

 be set up where the sea-water is always clear and equally dense, 

 as, for example, in some of the islands of the South Pacific Ocean, 

 or even in some of our English Channel Islands, then the water 

 could be drawn directly from the sea into the aquarium, and 

 perhaps the animals in the latter would derive benefit from the 

 microscopic food contained in the water not otherwise possible." 



The Crystal Palace Aquarium was established on those prin- 

 ciples which Lloyd insisted on as being correct ; in fact, it was 

 constructed under the supervision and direction of Lloyd himself. 

 The sea-water taken from the shore at Brighton was impure and 

 unfit for animal life when it first arrived at Sydenham, and it was 

 fouled still further — rendered poisonous indeed as regards the 

 purpose for which it was intended— by the absorption of lime 

 from the fresh cement used in the construction of the reservoir 

 and tanks. Yet, in due course, the action of the air absorbed 

 by the water, and of the vegetation which gradually developed in 

 the tanks from invisible germs present in the water, brought about 

 the purification of the latter, so that, to use Lloyd's expression, 

 " the water has become what it now is by keeping it and using 

 it." The water in the Crystal Palace Aquarium is the same that 

 was brought in an impure state from Brighton about twenty years 

 ago ; and it is kept circulating in the following manner : — There 

 is a huge reservoir, placed underground, containing 80,000 

 gallons of water ; and the series of large aquarium tanks con- 

 taining the living sea creatures contain 20,000 gallons more. 

 The water is driven by powerful pumping apparatus, continuously, 

 by day and night, from the reservoir through the whole series of 

 tanks, and back again into the reservoir. In the course of circu- 

 lation the water not only drops several inches from each tank into 

 the next one, but is also forcibly driven from pipes in jets down 

 to the bottom, or nearly to the bottom of each tank, by which 

 means the thorough aeration of the water is ensured. 



I might quote much additional evidence in support of the 

 plan of not changing the water in an aquarium, but the limits of 

 this paper will not allow it. When I first attempted to keep 

 living sea creatures, I changed the water periodically, at intervals 



