106 THE POPULAR SCIENCE MONTHLY. 



reserve, as we have seen, plays a double part in the economy : it is 

 a stock in abeyance, and it is the base of every present act. With- 

 out a reserve of mental energy, the mind can no more continue the 

 healthful exercise of its functions than a flabby muscle without to- 

 nicity can respond to the stimulus of strong volition and lift a heavy 

 weight or strike a heavy blow. 



The cause, or condition, which most commonly exposes the reserve 

 of mental energy to loss and injury is worry. The tone and strength 

 of mind are seriously impaired by its wearing influence, and, if it con- 

 tinue long enough, they will be destroyed. It sets the organism of 

 thought and feeling vibrating with emotions which are not consonant 

 with the natural liberation of energy in work. The whole machinery 

 is thrown out of gear, and exercise, which would otherwise be pleas- 

 urable and innocuous, becomes painful and even destructive. It is 

 easy to see how this must be. The longest note in music, the most 

 steady and persistent ray of light to use an old-fashioned expression 

 the tonic muscular contraction, are all, we know, produced by a 

 rapid succession of minute motive impulses or acts, like the explosion 

 and discharge of electricity from alternately connected and separated 

 points in a circuit ; in fact, a series of vibrations. Mental energy 

 doubtless takes the same form of development. If a disturbing ele- 

 ment is introduced by the obtrusion of some independent source of 

 anxiety, or if, out of the business in hand, the mind makes a discord, 

 confusion ensues, and for the time being harmonious action ceases. 

 Woi'king under these conditions in obedience to the will, the mental 

 organism sustains injury which must be great, and may be lasting. 

 The function of the warning sense is suspended; the reserve is no longer 

 a stock in abeyance, and it ceases to give stability to the mind ; the 

 rhythm of the mental forces is interrupted ; a crash is always impend- 

 ing, and too often sudden collapse occurs. The point to be made clear 

 is this : overwork is barely possible, and seldom, if ever, happens, 

 while the mind is acting in the way prescribed by its constitution, and 

 in the normal modes of mental exercise. The moment, however, the 

 natural rhythm of work is broken and discord ensues, the mind is like 

 an engine with the safety-valve locked, the steam-gauge falsified, the 

 governing apparatus out of gear ; a breakdown may occur at any in- 

 stant. The state pictured is one of worry, and the besetting peril is 

 not depicted in too lurid colors. The victim of worry is ever on the 

 verge of a catastrophe : if he escape, the marvel is not at his strength 

 of intellect so much as his good fortune. Worry is disorder, however 

 induced, and disorderly work is abhorred by the laws of nature, which 

 leave it wholly without remedy. The energy employed in industry 

 carried on under this condition is lavished in producing a small result, 

 and speedily exhausted. The reserve comes into play very early in 

 the task, and the faculty of recuperation is speedily arrested. Some- 

 times loss of appetite announces the cessation of nutrition ; otherwise 



