24 THE TONER LECTURES. 



vancing years, or when degenerative tissue changes are taking 

 place, violent exercise, even short, may be the cause of a tear 

 or injury; but I am speaking chiefly of the effect produced at 

 an age at which such exercises are usually resorted to. Still, 

 even then, as you have seen, there may be mischief, and you 

 will have learned how a number of occupations, and many of 

 our amusements, may lead to cardiac affection, sometimes by 

 textural alterations, produced in any part of the heart or great 

 vessels, but more usually by functional disturbance first, 

 which, in its turn, ends in dilated hypertrophy. A valve 

 trouble, when caused, is usually connected with the former 

 class of cases. Yet I believe that the dilated hypertrophy of 

 the second may terminate in valvular disease by the valve 

 having become incompetent to close the enlarging orifice, 

 which stretches as the cavities of the heart dilate and the mus- 

 cular walls thicken. That this really happens you will see 

 from the case I am about to relate to j'ou, which, though it 

 is not apposite as regards the cause of the dilated hypertrophy, 

 is so as to the subsequent development of valve disorder. 



B. L., a colored bo}', thirteen years of age, was admitted in 

 January, 1874, into the Pennsylvania Hospital. He stated 

 that he had pneumonia about four years ago, and that during 

 convalescence he was seized with acute rheumatic fever, which, 

 though it greatly crippled his joints, did not confine him to 

 bed. After his recovery he resumed his occupation of a fai'm 

 hand, and notwithstanding that he began to suffer from short- 

 ness of breath and palpitation for two months before he sought 

 admission into the hospital, worked laboriously for six weeks 

 more, until his feet began to swell. When examined he was 

 found to have considerable oedema of the extremities, much 

 distress in breathing, and a frequent, irregular pulse. The 

 praecordial space was notably prominent, and the impulse of 

 the heart heaving, and distinctly visible even at a distance. 

 The size of the organ was greatly increased ; the transverse 



