THE WONDEES OF THE SHOEE. 189 



sible,) and "by keeping on a cover. A piece of muslin 

 tied over will do ; but a better defence is a plate of 

 glass, raised on wire some lialf-incli above the edge, 

 so as to admit the air. I am not sure that a sheet 

 of brown paper laid over the vase is not the best of 

 all, because that, by its shade, also guards against 

 the next evil, which is heat. Against that you must 

 guard by putting a curtain of muslin or oiled paper 

 between the vase and the sun, if it be very fierce, or 

 simply (for simple expedients are best) by laying a 

 handkerchief over it till the heat is past. But if you 

 leave your vase in a sunny window long enough to 

 let the water get tepid, all is over with your pets. 

 Half an hour's boiling may frustrate the care of weeks. 

 And yet, on the other hand, light you must have, and 

 you can hardly have too much. Some animals cer- 

 tainly prefer shade, and hide in the darkest crannies ; 

 and for them, if your aquarium is large enough, you 

 must provide shade, by arranging the bits of stone 

 into piles and caverns. But without light, your sea- 

 weeds will neither thrive nor keep the water sweet. 

 With plenty of light you will see, to quote ISh. Gosse 



