Of Voluntary Motions

Symptoms.—The symptoms of the poisoning are headache, vertigo, nausea, extreme thirst, dry, burning skin, and general nervous confusion, with dilated pupils, loss of sight and of voluntary motion, and sometimes mania, convulsions, and death. 

The term paralyfis has generally been ufed toexprefs the lofs of voluntary motion, as in the hemiplegia, but may with equal propriety be applied to exprefs the difobediency of the mufcu-lar fibres to the other kinds of ftimulus as to tliofe of irritation or fenfation. 

The swimming of bacteria, the flowing motion of the ameba, the rapid contraction of voluntary muscles, and the slower movements of organelles and cytoplasm within cells all depend upon transduction of chemical energy into mechanical work. 

A particularly good example of how the working of the body is related to God s divine will is Boerhaave s discussion of the Aristotelian concept of sen-sorium commune in explaining the connection between the body and the mind as well as the connection of man to God. It is the place in the brain where all sense perception and impressions of the nerves come together and cause ideas, emotions, passions and voluntary motions. Boerhaave localised the sensorium commune in the place where all sensations originate, i.e. in all the points where the cerebral cortex and spinal marrow transfer into nerves. Boerhaave is very particular in stating that once the sensorium commune has set the body into motion it functions automatically, which means that for instance when someone decides to walk from Leiden to Amsterdam and back, the body will automatically do so. 

Voluntary motions. That exertion or change of the fenforium, which conftitutes defire or averfion, either fimply fub-fides, or is fucceeded by fibrous motions, it is then termed volition, and voluntary motions are thofe contradlions of the mufcular fibres, or of the organs of fenfe, that are immediately confequent to this exertion or change of the fenforium. 

Definition of vertigo, i. Some of the irritative fenfiial, or mufcular motions, which were ufually not fucceeded by fen-fation, are in this difeafe fucceeded by fenfation and the trains or circles of motions, which were ufually catenated with them, are interrupted, or inverted, or proceed in confufion. 2. The fenhtive and voluntary motions continue undifturbed. 3. The aflbeiate trains or circles of motions continue but their catenations with fome of the irritative motions are difordered, or in-vertedj or diffevered. 

I. I. Before w c commence this Section on Difeafed Voluntary Motions, it maybe neceffary to premife, that the word volition is not ufed in this work exacHy in its common acceptation. Volition isfaid in Se lion V. to bear the fame analogy to defire and averfion, which fenfation doss to pleafure and pain. And hence that, when defire or averfion produces any adiion of... 

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