276 TRANSMISSION. 



and tlie specimens placed one hj one in the bowls. 

 -Thus you will not only see which are alive and 

 healthy, and which are sickly or dead; but the weeds, 

 -shells, &c. will be rinsed from the sediment, which 

 has been abraded during the rattling of the specimens 

 in travelling. The specimens can afterwards be de- 

 posited in the Aquarium, their permanent home. 



Should any of the more delicate animals appear 

 much exhausted, they may often be restored by a 

 prompt aeration of the water around them. This is 

 most readily effected by means of the Syringe, as 

 I shall presently describe. 



If you can so arrange matters, it will be a useful 

 caution to allow your plants exclusive possession of 

 the Tank for a week or two, not putting any animals 

 in, until you see bubbles begin to form all over the 

 sides, bottom, and rock-work, when the sun-light 

 shines on them. This appearance will indicate a 

 growth of incipient vegetation, which will greatly 

 lessen the chance of death when the animals are 

 introduced. 



Finally, be moderate in your desire of dominion. 

 Do not overcrowd your Tank. It is far better to 

 have it but half occupied at first, and to add to its 

 population from time to time, than, by a too eager 

 desire to see it filled, make it a Black Hole of 

 Calcutta, and mourn over a host of corpses, the 

 wreck, perhaps, of a single night. Half-a-dozen 

 animals, averaging the bulk of a Periwinkle, or a 

 moderate-sized Sea- Anemone, to every gallon of water, 

 are quite enough to begin with. 



Geowth of Alg^. — Since the first edition of this 



