THE TrONDERS OF THE SHORE. 155 



face, (it should be done once a day, if possible,) 

 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 half inch 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 boil- 

 ing may frustrate the care of weeks. And yet, 

 on the other liand, light you must have, and 

 you can hardly have too much. Some animals 

 certainly prefer shade, and hide in the darkest 

 crannies ; and for them, if your aquarium is 

 large enough, you must provide shade, by ar- 

 ranging 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 sec, to quote Mr. Gosse once 



