ioo SCIENTIFIC ILLUSTRATIONS [Elo 



The Smallest Effort is not Lost. 



The smallest effort which is honestly put forth for the public 

 good must have an influence. It is never lost. It works mar- 

 vellously though we trace it not. Is any one incredulous 1 Let 

 him observe the effect on old ocean of one single act on the 

 part of a tiny inhabitant, and he will be astonished at the in- 

 fluence which a unit may exert. Let us suppose the ocean to 

 be perfectly at rest ; that throughout it is in a state of complete 

 equilibrium ; that with the exception of those tenants of the 

 deep which have the power of extracting from it the solid 

 matter held in solution, there is no agent in nature capable of 

 disturbing that equilibrium, and that all these fish, &c., have 

 suspended their secretions, in order that this state of a perfect 

 aqueous equilibrium and repose throughout the sea might be 

 attained. In this state of things the waters of the sea being 

 in perfect equilibrium a single mollusk or coralline, we will 

 suppose, commences his secretions, and abstracts from the sea- 

 water solid matter for his cell. In that act this animal has de- 

 stroyed the equilibrium of the whole ocean, for the specific 

 gravity of that portion of water from which this solid matter 

 has been abstracted is altered. Having lost a portion of its solid 

 contents, it has become specifically lighter than it was before ; 

 it must, therefore, give place to the pressure which the heavier 

 water exerts to push it aside and to occupy its place, and it 

 must consequently travel about and mingle with the waters of 

 the other parts of the ocean until its proportion of solid matter 

 is returned to it, and until it attains the exact degree of specific 

 gravity due to sea water generally. T. 



A Condition of Eloquence. 



Proper burning depends upon proper conditions. All bodies 

 which burn in the air, burn with increased brilliancy in oxygen 

 gas ; and many substances, such as iron, which do not readily 

 burn in the air, may be made to do so in oxygen. A red-hot 

 chip of wood, or a taper with glowing wick, is suddenly re- 

 kindled and bursts into flame when plunged into a jar of this 

 gas. Sulphur, which in the air burns with a pale lambent 

 flame, emits in oxygen a bright violet light ; and a small piece 



