THE MICROSCOPE. 293 
lose some rare and interesting creatures, should not only ex- 
amine the gathering as soon as possible after making it, but at 
frequent intervals as it stands on his table in the miniature aqua- 
rium near his window. 
A north window is the best place for the aquarium, because 
the light from that part of the sky is more diffused and more 
even in quality. Direct sun-light will surely kill the Infusoria, 
as well as much larger and presumably more hardy aquatic 
creatures. After a microscopical collecting trip, never place the 
bottles in the sun for any length of time. There is also another 
common practice that should be avoided in this connection. 
A gentleman once took a large quantity of water from what 
appeared to be a pool rich in microscopic life. He carefully 
filled the bottle to the brim, foreed in the cork, and the next 
morning brought the gathering to me. He was kind but ignor- 
ant. The bottle contained not a single living creature, but its 
contents were odoriferous and repulsive to the last degree. The 
water had been rich in animal life, but he unwittingly had killed 
every aquatic creature in his collection. He had smothered 
them. They were drowned, dead, corrupt. Because Infusoria 
and other animals live in the water is no reason that they 
should not need air. They cannot exist without air. Therefore 
be careful not to fill the bottle, and if it must be corked, see that 
ample air space is left between the surface of the water and the 
stopper. 
A specie jar or glass fruit dish makes a good microscopical 
aquarium, into which the gathering may be poured and the 
contents left to themselves, a piece of glass being placed over the 
mouth to prevent evaporation, although this is not strictly neces- 
sary. Such an aquarium presents a wider surface to the air, 
it is so shallow that its microscopical contents may be 
more readily captured, and it occupies less space than the or- 
dinary vessels offered by the dealers. I have been in the habit 
of selecting such jars as could be bought for from ten to fifteen 
cents each, several of which may be used at once for purposes 
of experimentation, or for the cultivation of different classes of 
microscopic animal and vegetable life. Such an aquarium, if 
kept near a north window, will thrive all winter, giving the 
microscopist a continuous supply of interesting living objects, 
not necessarily confined to Infusoria, but if he wish, embracing 
many groups of microscopic creatures. 
