AND THEORIES. 



287 



to take place during the operation of the irritation. 

 Such phrases must be fully explained before they can 

 be accepted as explanations of the phenomena to 

 which they refer. Pus, it is said, results from " abnor- 

 mal stimulation of the tissues ;" but the meaning of 

 the term stimulation is not defined, and we are left as 

 much in the dark as by our many predecessors who 

 were contented to attribute all morbid phenomena to 

 the operation of mysterious and inexplicable agents 

 and forces. Lister further remarks, that no stimulus 

 can alone induce healthy tissues to suppurate, but that 

 when they have been " gradually degraded " under 

 the influence of " protracted abnormal stimulation 

 into the most imperfect of all Kssues, which, when we 

 see it at the surface of a sore we term granulations, (!) 

 that they are in a condition if further stimulated to 

 give birth to the still lower progeny of pus-corpuscles."* 

 Here is a whole string of hypotheses, not one of 

 which has been or can be substantiated. Such a 

 pathology appears to me wholly retrograde and inde- 

 fensible. Pus formation is attributed to irritation, 

 and the irritation generally at any rate, is supposed 

 to resuir_from the presence of decomposing organic 

 matter. 



Professor Lister endeavours to show how his theory 

 is borne out by experience. He remarks : " My ex- 

 perience leads me to believe that if, when the dress- 



* " Remarks on a Case of a Compound Dislocation of the Ankle," 

 p. 26. 1870. 



