Volcanoes 

 Walking 



SCIENTIFIC SIDE-LIGHTS 



742 



when suddenly the sleeping force beneath is 

 aroused and some fresh volcanic outlet is 

 opened through the ground. When Vesuvius 

 woke up from its protracted slumber, to 

 swallow up Pompeii and the other towns 

 lying round its base, it had rested for some 

 centuries, and the Romans looked upon it 

 as nothing but a lifeless mountain like the 

 peaks of the Apennines. On the other hand, 

 it is very possible that some craters from 

 which steam and jets of gas are still esca- 

 ping, or which have thrown out lava dur- 

 ing the historic era, have entered decisively 

 into a period of repose, ceasing somehow 

 to maintain their communication with the 

 subterranean center of molten matter. The 

 number of vents which serve for the erup- 

 tion of lava can therefore be ascertained 

 in a merely approximate way. Humboldt 

 enumerates 223 active volcanoes; Keith 

 Johnson arrives at the larger number of 

 270 ; but this latter estimate is 



probably too small. RECLUS The Earth, pt. 

 iv, ch. 62, p. 432. (H., 1871.) 



3674. VOLITION A FORCE Will 

 Draws on Latent Supplies in the Body Ap- 

 plication and Direction of Energy. Is there 

 nothing in the human body to liberate it 

 from that chain of necessity which the 

 law of conservation coils around inorganic 

 nature? Look at two men upon a moun- 

 tainside, with apparently equal physical 

 strength; the one will sink and fail, while 

 the other scales the summit. Has not voli- 

 tion, in this case, a creative power ? Physic- 

 ally considered, the law that rules the oper- 

 ations of a steam-engine rules the operations 

 of the climber. For every pound raised by 

 the former, an equivalent quantity of its 

 heat disappears; and for every step the 

 climber ascends an amount of heat, equiva- 

 lent jointly to his own weight and the 

 height to which it is raised, is lost to his 

 body. The strong will can draw largely 

 upon the physical energy furnished by the 

 food; but it can create nothing. The func- 

 tion of the will is to apply and direct, not 

 to create. TYNDALL Heat a Mode of Mo- 

 tion, lect. 17, p. 531. (A., 1900.) 



3675. VOLITION AS ESSENTIAL TO 

 LIFE AS AUTOMATISM Mow Has His 



Own Part to Play Voluntary and Involun- 

 tary Processes Blend in Perfect Living. We 

 find that in maintaining this natural life 

 Nature has a share and man has a share. 

 By far the larger part is done for us the 

 breathing, the secreting, the circulating of 

 the blood, the building up of the organism. 

 And altho the part which man plays is a 

 minor part, yet, strange to say, it is not 

 less essential to the well-being, and even to 

 the being, of the whole. For instance, man 

 has to take food. He has nothing to do 

 with it after he has once taken it, for the 

 moment it passes his lips it is taken in 

 hand by reflex actions and handed on from 

 one organ to another, his control over it, 



in the natural course of things, being com- 

 pletely lost. But the initial act was his. 

 And without that nothing could have been 

 done. Now whether there be an exact anal- 

 ogy between the voluntary and involun- 

 tary functions in the body and the corre- 

 sponding processes in the soul we do not at 

 present inquire. But this will indicate, at 

 least, that man has his own part to play. 

 DEUMMOND Natural Law in the Spiritual 

 World, essay 7, p. 228. (H. Al.) 



3676. VOLITION INCARNATED IN 

 THE BODY Habitual Voluntary Movements 

 Become Automatic The Motor Memory. 

 Each time a voluntary action is performed, 

 an impulse is discharged by the will to the 

 muscles. . . . The mind being concerned 

 with the execution of the movement, and 

 not with the individual muscles, the further 

 elaboration of the impulse is brought about 

 by the ganglion cells of the motor memory 

 centers. 



Each time the higher faculties send im- 

 pulses to several of these governing cells at 

 once, an association is formed between them, 

 resulting in a permanent modification of 

 their constituent protoplasm. By repetition 

 of the same movement, this association of 

 the cells becomes stronger and stronger, un- 

 til a very slight stimulus is required to 

 bring about the movement. 



It is this modification of their protoplasm 

 and association of the cells which consti- 

 tutes the motor memory. The motor mem- 

 ory thus bears the same relation to the out- 

 going impulses of the mind as the sensory 

 memory does to the ingoing impressions. 

 The motor memory has, therefore, only to 

 do with voluntary movements, or move- 

 ments which have been primarily voluntary, 

 but have become secondarily reflex. EL- 

 DRIDGE-GREEN Memory and Its Cultivation, 

 pt. i, ch. 4, p. 25. (A., 1900.) 



3677. VOLITION WEAKENED BY 



HASHISH Control and Coordination of 

 Thought Lost. One of the first appreciable 

 effects of the hashish is the gradual weak- 

 ening of that power of volitionally control- 

 ling and directing the thoughts, which is so 

 characteristic of the vigorous mind. The 

 individual feels himself incapable of fixing 

 his attention upon any subject; the conti- 

 nuity of his thoughts being continually drawn 

 off by a succession of disconnected ideas, 

 which force themselves (as it were) into 

 his mind, without his being able in the least 

 to trace their origin. These speedily engross 

 his attention, and present themselves in 

 strange combinations, so as to produce the 

 most impossible and fantastic creations. By 

 a strong effort of the will, however, the orig- 

 inal thread of the ideas may still be recov- 

 ered, and the interlopers may be driven 

 away; their remembrance, however, being 

 preserved, like that of a dream recalling 

 events long since past. These lucid inter- 

 vals become progressively of shorter dura- 



