OSSIFICATION OF AKTEFJES. 10 



contracted arteries, such as lead to senile gangrene, said : 

 " Such patients walk a short distance very well, but when they 

 attempt more than this, the muscles seem to be unequal to the 

 task, and they can walk no further. The muscles are not 

 absolutely paralysed, but in a stage approaching to it. The 

 cause of all this is sufficiently obvious. The lower limbs require 

 sometimes a larger and sometimes a smaller supply of blood: 

 During exercise a larger supply is wanted on account of the 

 increased action of the muscles ; but the arteries being ossified 

 or obliterated, and thus incapable of dilatation, the increased 

 supply cannot be obtained. This state of things is not peculiar 

 to the lower limbs. Wherever muscular structures exist the 

 same cause will produce the same effect. Dr. Jenner first, and 

 Dr. Parry of Bath afterward, published observations which were 

 supposed to prove that the disease which is usually called 

 'angina pectoris' depends on ossification of the coronary 

 arteries. . . . Wlien the coronary arteries are in this condi- 

 tion they may be capable of admitting a moderate supply of 

 blood to the muscular structure of the heart ; and as long as the 

 patient makes no abnormal exertion, the circulation goes on well 

 enough ; when, however, the heart is excited to increased action, 

 whether it be during a fit of passion, or in running, or walking 

 upstairs, or lifting weights, then the ossified arteries being 

 incapable of expanding so as to let in the additional quantity of 

 blood, which, under these circumstances, is required, its action, 

 stops and syncope ensues ; and I say that this exactly corre- 

 sponds to the sense of weakness and want of muscular power 

 which exists in persons who have the arteries of the legs- 

 obsLructed or ossified."* 



But the syncope and stoppage of the heart mentioned by 

 Brodie are not the only consequences of impaired cardiac 

 nutrition. The heart may be still able to carry on the circula- 

 tion, but the patient may suffer intense pain in the process. 

 The outside of the heart was found by Harvey to be insensible 

 to light touches, but the inside of the heart appears to be much 

 more sensitive either to touch or pressure, and the internal pres- 



* Lectures on Fatlwlogy and Surgerij, hj Sir Benjamin Brodie, London, 

 1846, p. 3G0. 



C 2 



