METHODOLOGICAL INTRODUCTION. 5 



been assumed. By these means a number of chemical fictions have 

 supplanted the fancies of that speculative natural philosophy which 

 in earlier times encumbered the study of physiology and pathology, 

 and have plunged medicine into the midst of a new labyrinth of 

 untenable theories. 



We have indicated a further cause of the partial failure of the 

 application of chemistry to vital phenomena, in the imperfect causal 

 connexion among the different branches of natural science, without 

 which there can be no proper insight into the course of dif- 

 ferent phenomena, or any recognition of the complete vital process. 

 This is especially the case in reference to pathologico-chemical 

 enquiries, in the majority of which the data yielded by pathological 

 anatomy, and the diagnosis thus afforded, have been too little 

 regarded, whilst the adherents of the pathologico-anatomical school 

 have made free use of chemical phrases and fictions, without an 

 adequate acquaintance with the general science of chemistry. 

 If chemical investigations regarding objects belonging to patho- 

 logical anatomy would aspire to a scientific value, and if they are 

 to afford any true elucidation of pathological processes, it will 

 assuredly be admitted that the question should be adequately con- 

 sidered from an anatomical and diagnostic point of view. Yet 

 every day presents us with instances of the most flagrant neglect 

 of this self-evident proposition. How frequently we hear of the 

 chemical examination of diseased bones without any regard to a 

 diagnosis at all in accordance with the present condition of patho- 

 logical anatomy ! What numerous analyses have been made of the 

 bones in osteomalacia, notwithstanding that the morbid appear- 

 ances of these bones vary so much as to render a definite 

 diagnosis a matter of extreme difficulty to the pathological ana- 

 tomist ! We even more frequently meet with similar inconsis- 

 tencies in the investigation of diseased animal fluids. Here, as in 

 the statistical method of observing diseases, none but the simplest 

 form of a disease should be made the subject of such enquiries. 

 Yet the causal results yielded by an examination of the urine and 

 the blood in the most complicated forms of disease, are frequently 

 made the sole grounds for drawing conclusions regarding the mor- 

 bid process itself. In many cases even the true diagnosis of the 

 disease has not been given. Thus, for instance, we are told that the 

 blood has been analysed in typhoid pneumonia, yet when we read 

 the history of the case, we find that the disease was neither ordinary 

 abdominal typhus with pneumonic exudations, nor what is termed 

 pneumo-typhus, but simple pneumonia with cerebral symptoms. 



