16 



Dr. C. Bolton. Physiological Action of a [Mar. 20, 



Heart. — This organ is flabby and dilated in both its left and right sides. 

 Its cavities are full of blood, dark in colour in the right ventricle and bright 

 red in the left ventricle. The large vessels are also full of blood. The heart 

 evidently stops in diastole. 



As a post-mortem phenomenon the left ventricle may pass into systole. 



If the unfiltered or uncentrifugalised solution has been injected in large- 

 doses, the blood in all the cavities of the heart is liable to be found clotted 

 immediately after death, the clot being black in the right cavities and red in 

 the left cavities. The large veins are full of dark clot, and the aorta contains- 

 bright red clot. The clotting extends up to the jugular veins. The 

 pulmonary vessels contain fluid blood, and the portal vein may contain 

 a few clots, but here the blood as a whole is fluid. 



If the solution has been centrifugalised or filtered previous to injection no 

 clotting occurs. In all cases the blood clotted normally when removed 

 from the body. In one case which had received four injections extending 

 over a period of six days evidence of a gradual heart failure was found in th& 

 presence of dropsy of the mediastinum and slight bilateral hydrothorax. 



Central Nervous System. — The spinal cord and bulb were stained by 

 Nissel's method in one case, which had received several injections of the- 

 poison extending over a period of several days. The nerve ceils were normal 

 in all parts. 



5. Mode of Action. 



In this investigation the animals used were cats and rabbits. Ether was- 

 in all cases administered before and during the experiments. 



Neither morphia nor curari was previously administered as it was thought 

 that it would be better to rely entirely upon ether, and the results have 

 justified this procedure. In three cases the initial blood pressure was very 

 high, probably owing to the ether, but this did not interfere with the- 

 results, because the relative readings of the blood pressure before and after- 

 injection were only required and not the absolute readings. 



The mean arterial blood pressure was taken in either the carotid or femoral 

 artery and recorded by means of Brodie's modified kymograph. The tube- 

 used to connect the artery with the mercurial manometer was filled withv 

 a solution of MgS0 4 (sp. gr. 1046). The respirations were also recorded by 

 means of a tambour, and the time marked in seconds. 



Artificial respiration was employed through a tracheotomy tube in the- 

 spinal-cord experiments, the air being blown through a bottle containing 

 ether. A secondary coil and bichromate battery were used for the stimulation 

 experiments. 



