440 Prof. C.S. Sherrington and Miss S. C. M. Sowton. [Dec. 30, 
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Rheonome 
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Tenet 
Fic. 4.—Arrangement of Apparatus for Comparing Effect of Galvanic Stimulation by 
Rotating Rheonome with that of Faradisation from ordinary Inductorium. 
C., commutator in galvanic circuit; .B., resistance box; ZnSO,, saturated zinc 
sulphate solution in trough of rotating rheonome ; ¢ and 7’, travelling electrodes in 
trough in rotating rheonome. Rheonome, rotating rheonome, only a small arc of the 
complete circle being indicated. A./V., afferent nerve with non-polarisable electrodes 
applied; Sp.C., spinal cord; JV., nerve of vasto-crureus muscle; V.C.IZ, vasto- 
crureus muscle with tendon attached to myograph. 
They differ from the reflexes usually resulting from weak stimuli in several 
ways. With weak stimuli of other kinds it is usual for the reflex contraction 
to decline soon, even during the continuance of the stimulation, in one or 
other of twoways. (1) Either there ensues “ fatigue,” which though slight is 
yet sufficient to cancel soon the excitation of a stimulus which is itself but 
little above threshold value. This is the phenomenon that accounts for 
the, at first sight, paradoxical result that the reflex contraction evoked by a 
quite weak stimulus tends to tire out sooner than that evoked by a strong 
stimulus. Fig. 6 exemplifies this result in reflex contractions of a flexor 
muscle evoked by faradic stimulation of the afferent nerve,* (2) Another way 
in which decline of a weak reflex contraction ensues rapidly during con- 
tinuance of the stimulus is, in the extensor decerebrate preparation, by 
supervention of reflex inhibitory relaxation, the character of the reflex result 
* Of. also Sherrington, ‘ Integrative Action of the Neryous System,’ 1906, p. 219. 
