156 THE POPULAR SCIENCE MONTHLY. 



But we have not touched bottom ; and maybe these are some of His 

 ways which are past finding out. So, having reached the deep waters, 

 we will take that preacher's exordium to his knotty text, and make it 

 the peroration of our discourse : " Brethren, there is mighty deep 

 Scripture here ! " 



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INITIATORY FORCES. 



By GEORGE ILES. 



LAST September, when the operations for the removal of the ob- 

 structions at Hell-Gate, in the harbor of New York, had culmi- 

 nated in the completion of the great labyrinth of tunnels, and the 

 storing therein of a larger quantity of explosives than had ever been 

 used at once before. General Newton, the chief-engineer, at the ap- 

 pointed moment told his little child to gently push a telegraph-key. 

 She did so; her tiny impulse closed the circuit in many hundred gal- 

 vanic cells ; and these, by inflaming the metallic wires in contact with 

 the explosives, freed in an instant the tremendous power which had 

 been slumbering under the peaceful waters. 



Perhaps in the whole realm of human achievement no more striking- 

 example of an initiatory force has ever been given than this. And if 

 it had not had an appearance of trifling, it would doubtless have been 

 quite possible for matters to have been so arranged that a fly impris- 

 oned in an inverted wineglass could by the vibration of its little wings 

 have brought two delicate electric conductors into contact say two 

 moistened silken filaments and have thus pulled the trigger which, 

 in the course of its efiects, would have made Hell-Gate navigable. 



In Nature and art we find abundant examples of the same kind : 

 gigantic forces, perfectly quiescent and even useless, until some slight 

 additional force of the proper kind or intensity precipitates the most 

 violent changes. And this necessity for an outside initiatory force is 

 generally found with great power to maintain action once begun. 

 Carbon, and fuels of all kinds, are instances in point. As a rule, they 

 are but little altered by contact with the atmosphere, even for years ; 

 but a match has only to be applied to a few shavings, and a mine of 

 coal may be set on fire so thoroughly that it continues burning for 

 half a century. A prairie or forest may be dried up by drought until 

 leaves and twigs are brittle and dead, but all is calm until a chance 

 spark from a locomotive or a tobacco-pipe starts a fire that may de- 

 vastate square leagues of territory in its course. 



In all cases of unstable equilibrium and such abound in Nature 

 a very small impetus may produce great consequences ; and this not 

 only in amount but direction. With an avalanche perched on a monn- 



