THE AQXTAEIUM. 



A more useful aquarium ttan any yet mentioned is one 

 formed of slate and plate-glass only (Fig. 8). It can be 

 made by an amateur without mucb difficulty. But perhaps 

 the tank most suitable for its purpose is Pig. 9. One side 

 only is of glass ; the others can be made of wood lined with 



Fig. 9. 



glass, or of slate only. The former method is the easier and 

 cheaper to construct, the latter the more serviceable. 



Explicit dii-ections for making aquaria similar to those 

 shown at Figs. 6, 7, 8, and 9, are given in Chapter II. 



