FORM, SIZE, AND MATERIALS. 255 



If a cylindrical form of vessel be preferred, it can 

 be obtained without any material but glass in the 

 construction. A very pleasing aquarium, which has 

 the advantage of cheapness, is greatly in request, 

 formed of a propagating glass turned upside down, 

 and set on a stand of polished mahogany or rosewood. 

 This form has cylindiical sides, and a rounded bottom, 

 terminating in a knob, which, being inserted into a 

 cavity in the stand, gives security to the whole. The 

 bottom should be covered with sand or earth to a 

 height sufficient to bring it up to the level of the 

 cylindrical sides, for the convenience of observation. 

 Vessels of this shape are now made up to twenty 

 inches in diameter. 



Messrs. Lloyd and Summerfield, of Birmingham, 

 have recently published some very elegant designs for 

 Aquaria. They construct rectangular tanks wholly of 

 glass, the bottom, the corner-pillars, and the bars which 

 connect them above, being all of that material. Their 

 scale of prices, however, seems very high. Speci- 

 mens of their productions may be seen at the Crystal 

 Palace, and at 35 and 36, Aldermanbury, London. 



Confectioners' show-glasses are very suitable for 

 small specimens ; they are usually about twice as 

 high as broad, and are therefore the more gTaceful. 

 These afford peculiar facilities for the examination 

 of their contents wdth a lens, as they can be easily 

 moved round, and may be placed before a candle or 

 lamp for nocturnal investigations. They may be had 

 of various sizes, from three to eight inches in diameter; 

 six inches is a very convenient size. I have made 

 very pretty vases for minute objects by taking the 



