220 DISEASES OF THE PARENCHYMA OF THE LUNG. 



Not unfrequently, persons born with well-nourished, vigorous con- 

 stitutions evince a decided tendency to consumption from the effect 

 of some other disease, whereby the prehension or assimilation of their 

 food is prevented, or which is undermining their health in some other 

 way. Many patients with ulcers of the stomach, with strictures of 

 the oesophagus, lunatics who persistently refuse their food, finally die 

 consumptive. In like manner persons afflicted with diabetes mellitus, 

 obstinate chlorosis, or tertiary syphilis, ultimately die of pulmonary 

 phthisis. Among acute disorders, typhus is apt, when protracted, to 

 leave behind it a predisposition to this disease. 



To these predisposing causes, acquired through other affections, 

 may be added those which are provoked by persistent suckling, 

 onanism, venereal excess, by depressing or exciting mental influences, 

 immoderate study, and inconsolable grief. 



I regard the wide-spread doctrine that consumption is solely 

 dependent upon a diathesis, from which it proceeds independently of 

 all so-called " exciting causes," as equally gratuitous and dangerous. 

 The circumstance that the admission of the origin of this disease 

 from external irritation stood in direct conflict with a theory which 

 no one dared to gainsay, has manifestly prevented an unbiassed inter- 

 pretation of facts. The deliberate assertions of Laennec and his 

 pupils, that " catching cold," and other irritation, had no influence in 

 producing pulmonary consumption, and that it never arose from a 

 neglected catarrh, has had the most pernicious effect, both upon 

 prophylaxis and treatment of the disease. 



The exciting causes which give rise to consumption, where predis- 

 position to it exists, consist, as I believe, in all influences capable 

 of producing fluxionary hyperaemia of the lungs and bronchial catarrh. 

 I therefore refer to what has been stated already as to the etiology 

 of the latter. 



The popular idea, that consumption is often the consequence of 

 indulging in cold beverages while the body is overheated, I used 

 formerly to look upon as a fable, or at least as a badly-interpreted 

 fact. But, as I gradually emancipate myself from the teachings of 

 Laennec^ I dare no longer maintain such absolute views, and am 

 forced to admit that a sudden chilling of the stomach is quite as ca- 

 pable of inducing catarrhal and pneumonic processes, and hence con- 

 sumption, as is a sudden cooling of the skin. The fact that large 

 draughts of cold water have been swallowed with impunity by innu- 

 merable persons in an overheated condition, by no means contradicts 

 the suppostion that such a cause may now and then be followed by 

 serious results. So, too, sudden chilling of the skin is not followed 

 by sickness in all cases, but only occasionally ; and since it is noi 

 understood how this result occasions derangement in remote organs 



