49 



STRUCTURE INDICATES FUNCTION. 



These minute particulars as to the structure of the frog- 

 cushion — and they could have been made more minute still — 

 I deem of importance, as they point unmistakably to its func- 

 tions. " Men do not gather grapes from thorns, nor figs from 

 thistles ; " but they sometimes commit the equally egregious 

 blunder of attributing functions to organs and textures which 

 are altogether foreign to their destined purposes, through im- 

 perfect acquaintance with their intimate composition and organ- 

 ization. These considerations, together with the desire I en- 

 tertain that the sub-structure of my theory and practice in regard 

 to diseases of the feet shall be laid sufficiently broad and 

 deep in the facts of anatomy and physiology must'be my apol- 

 ogy, if any were needed, for dwelling so long upon th£ compo- 

 sition and organization of tissues. 



FUNCTIONS OF THE FROG. 



The highly important functions of the frog have yet to be 

 considered. The horny frog is evidently designed to receive 

 pressure externally, as without this there would be no basis 

 afforded for the resilient movements of the internal spring- 

 cushion — that is to say, the sensitive frog. The most familiar 

 illustration of this view is the following: Take the spring- 

 cushion of a carriage, or the spring-mattress of a bed. It will 

 be seen that the spiral spring is fastened by one end to a solid 

 base or frame-work. The full action of the spring is thus ob- 

 tained ; but if the solid base is removed, and a yielding base 

 substituted, the action of the spring is neutralized in proportion 

 to the yielding character of the base ; in other words, much of 

 its resilient action is lost, and the body, sitting or recumbent 

 upon either, would sink to a lower level and find less springi- 

 ness on the seat or the bed. 



IMPORTANCE OF A HEALTHY FROG. 



Thus, the sensitive frog is the spring-cushion, and the horny 

 frog its base of action, when these tissues and functions are un- 

 interfered with. 



