1 86 BIOLOGICAL PHYSICS 



consists in the temporary arrest of the complete reign of 

 gravitation and inorganic laws by the whilom erection of 

 an organic barrier^ by, or in, virtue of vital energy, 

 operating through formative impulse, along definite lines 

 of organic accretion, to living organisms such living 

 organisms being ultimately overtaken and subdued by 

 .the ''all-prevailing" inorganic laws, but not, as a rule, 

 before they have secured their survival, and the perpetua- 

 tion of life, by transferring that life, in sufficient proportion, 

 to maintain an effective resistance, in the perpetual strife 

 of organic, and inorganic forces, and to secure the con- 

 tinuous existence of life, active intelligence, moral energy and 

 purpose, and future destiny. 



The principle of the accelerative influence of the 

 vacuum, and vacuole, in the economy of circulation 

 throughout the body, seems to us to find employment 

 in the phenomena of muscular action. Thus, muscular 

 contraction, as displayed by individual muscle fibres, is 

 rhythmic, i.e. rest, and contraction, alternate with each 

 other, the rest allowing the muscle fibre to recover itself, 

 both as regards substance and energy, and the contraction 

 displacing both substance and energy along the lines of 

 least resistance, each contraction, and period of rest, 

 constituting the two halves of a whole operation, which, 

 repeated, and repeated, make up the life experience of 

 every muscle fibre, striped, and unstriped. To use a 

 familiar simile, we might compare the contraction of a 

 striped muscle fibre to the reduction of a fully extended 

 accordion, or concertina, to its ordinary proportions, or 

 what it is in a state of rest, by the withdrawal of impedi- 

 ments to its resumption of that position, or by the 

 application, it may be, of a compressing force. During 

 this change the interior of the instrument is emptied of 

 contained air, and collapse of it is the consequence. In 

 the case of contraction of a muscle fibre due to the effect 

 of nerve energy on the contractile substance of the fibre, 

 the mtra-fibril contents are, or must be, more or less, 

 displaced, according to the intensity of the determining 

 influence, with the result, that the fibre, on the re-attain- 

 ment of its normal proportions, must give rise within 

 itself to the formation of a series of discal vacuoles 



