6 THE AQUARIAN NATURALIST. 



any depth they may desire, or even to ascend the 

 sloping back and emerge from the water. 



Thirdly, it admits of a much larger surface being 

 exposed to the action of light ; and, 



Fourthly, the sloping top allows the water which 

 condenses on the glass to trickle off and return to 

 the aquarium, without first resting on the zinc or iron 

 framework. It need hardly be suggested, that the 

 sloping back is to be covered with light rock-work 

 extending to a short distance above the water-line. 



Let it not, however, be supposed, that although 

 the form of tank above described by Mr. Warington 

 may be the best in its general construction, it is by 

 any means indispensable ; tanks of all shapes and 

 sizes are now to be readily procured at moderate 

 prices adapted to all tastes. Yet even these are 

 luxuries : a common show-glass, such as we see in 

 confectioners' shops, a large glass gold-fish globe, or, 

 in default of these, a common earthenware pan will 

 be found to answer every end as far, at least, as 

 relates to the preservation of specimens for the pur- 

 poses of scientific research. 



The common propagating glasses used by gardeners, 

 and which may be procured of almost any size, form 

 admirable substitutes for the more expensive plate- 

 glass tank; and the broad shallow glass pans now 

 generally in use for holding milk, will be found in 

 many cases even more convenient than deeper vessels. 

 They say that it is only the bad workman who finds 

 fault with his tools, and upon the same principle the 

 real naturalist will never be at a loss for an appropriate 

 vessel as long as a dish or a basin can be obtained. 



