124 BULLETIN OF THE 



123d Meeting. April 21, 18TT. 



Yice-President Taylor in the Chair. 



Mr. A. F. A. King, in continuance of his former paper (read 

 February 24, ISttj, presented remarks showing 



THE CONSERVATIVE INFLUENCE OF DISEASE AS ILLUSTRATED IN 

 THE PHENOMENA OF PULMONARY PHTHISIS. 



(ABSTRACT.) 



Spealving generally, and in conformity with the views pre- 

 viously presented, he concluded: 1st. That the primary cause 

 of conservative organic change, was change of environment which 

 necessitated modification or function. 2d. To prevent such 

 changes taking place, the natural environment must be continued. 

 3d. To arrest tlae progress of commencing modification, the new 

 environments must be removed — the eld ones restored. 4th. When 

 this last cannot be done, the structural modifications resulting 

 from the new environments must be conducted to their designed 

 completion. 



Successfully to carry out this course a knowledge of the adaptive 

 relationship between the new structures and new environments 

 must be acquired. 



To this end the case selected for study must be a typical and 

 completed oae, characterized chiefly by the qualities of latency 

 and chronicity — comparative absence of symptoms and slowness 

 of growth. The points to be ascertained are : 1st. Plow has the 

 modified organ been made to differ, in function, from the physio- 

 logical it/iniodified organ ? 2d. Wiiat environing conditions have 

 rendered the functional modification necessary or desirable for 

 the prolongation of life ? 



To answer these inquiries, animals of different species and 

 variety may be studied with a view to discover individuals 

 whose organs, in their physiological state, resemble those of 

 the modified human organism. The environments natural to 

 such animals would necessarily resemble those producing re- 

 sembling modification in man; hence the cause of the acquired 

 modification in man would be thus reached. 



Again, by studying individuals having structural peculiarities 

 exactly opposite to those observed in the human specimen, we 

 learn by contrast what we before learned by resemblance. 



In applying this method of study to pulmonary phthisis, after 

 selecting a "typical" completed case of the disease for special 

 examination, we find the structural changes to be (chiefly) : dilata- 

 tion of the bronchi with chronic peribronchitis ; thickening and 

 adhesion of the pleura; obliteration of air-vesicles and capillary 

 bloodvessels in the lung, the normal lung tissue being substituted 

 by a hyperplasic growth of connective, or fibrous, or even fibro- 



