LIFE IN THE OCEAN. 61 
in a closed cylinder placed below the level of the aquarium, makes 
it ascend, and enter with great force into a reservoir, into which it is 
thrown from a small jet. The sea water thus pressed absorbs a 
portion of the air, which is drawn with it into the reservoir. A tube 
placed in a corner of the reservoir receives the overflow, and 
conducts it into a closed carbon filter, whence it passes into a gravelly 
underground reservoir, returning again to the closed cylinder. The 
water is once more subjected to the pressure of air, and again 
ascends to the aquarium. The cylinder being underground, a 
temperature equal to about 16° Centigrade, which is nearly the 
uniform temperature of the ocean, is easily maintained. During 
winter the aquarium is heated artifically. 
We ought not to conclude our remarks on this subject without a 
passing allusion to the large aquarium at the Sydenham Palace, and 
to the still larger one more recently opened at Brighton, which, for 
abundance of specimens and tastefulness of arrangement, far surpass 
anything of the sort previously attempted in England. 
