538 COMPETENCE OF VALVES. 



througli them, and the pressure inside the ventricle may be raised 

 to any necessary degree. If the heart be healthy, no waier will 

 escape until the pressure becomes excessive, and then a small jet 

 may be seen to issue from between the valves. By connecting 

 the tube leading from the water supply to the heart with a 

 mercurial manometer, the pressure at which the valves become 

 incompetent may be at once ascertained. The ventricle may be 



Fig. 103.- 



then cut open, the nozzle removed, and the valves inspected in 

 the usual way. I do not claim the idea as an entirely new one. 

 The instrument has doubtless been used in various forms many 

 times before, but the form in which I employ it is exceedingly 

 cheap ; and the time required for its application is very short, 

 a couple of minutes sufficing to ascertain the competency of 

 both valves, and it does not in the least injure the heart if it 

 be wished to preserve it as a specimen afterwards. It may 

 therefore, I think, be more widely employed than any other 

 instrument of the sort, and may thus lead to the discovery of 

 very interesting results. 



* This figure was not in tlie original paper. 



