The old question of the influence of sympathetic nerve fibers on the so-called tonus of skeletal muscle has recently attracted renewed attention, in view of a somewhat widespread agitation for surgical relief of spastic paralysis by "ramisection." A great deal of experimental work has been directed to this problem, and a still larger amount of speculation has been expended on it. Yet the problem seems to be still in a decidedly unsettled state.
So much of the previous work has been inconclusive and so conflicting has been the testimony that we have attempted to clarify the subject by emphasizing quantitative methods of experimentation, by searching carefully for all possible sources of experimental error, and by critically examining our results and the various arguments in the light of modern knowledge of nerve-muscle physiology. Perhaps the chief justification for adding to the already heavily burdened literature of the subject is the uncertainty