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The author first dwelt upon the occurrence of paroxysmal 
dyspneea or asthma, and after discussing the effects which would 
be produced if the minute branches of the pulmonary artery 
were suddenly contracted, and the general symptoms and phy- 
sical signs which would accompany such an event, he shewed by 
reference to cases recorded by other observers, and from in- 
stances which had come under his own observation, that the 
theory was supported by facts. He next referred to epilepti- 
form convulsions and uremic coma, and pointed out why, in 
some cases, convulsions might occur, and not in others; owing 
to the predominance of one or other of the above-mentioned 
factors. He then went on to say, that, although cerebral apo- 
plexy not unfrequently occurred in chronic Bright’s disease, 
where there was atheromatous degeneration of the arteries; yet 
that, independently of this, the apoplexy might be caused by 
the velocity of the blood through the minute tubes being re- 
tarded, (the velocity through a tube varying as the square of the 
radius of the section,) and so leading to the formation of a small 
coagulum of fibrin or a thrombosis. There would then be com- 
plete obstruction, and consequently the greatest possible pres- 
sure would be brought to bear on the arterial wall and result 
very probably in rupture. This also, he contended, explained 
the production of pulmonary apoplexy, and minute apoplexies 
in the kidneys and spleen, or hemorrhagic infractions occurring 
in chronic Bright’s disease, where no valvular mischief of the 
heart or endocardiac disease existed. 
Dr BrapBury thought the symptoms mentioned by Dr 
Latham were explicable on the supposition that after Bright's 
disease had set in, thrombosis of the heart had taken place. He 
described a case of pulmonary apoplexy which he had recently 
examined, where a large blocking had been caused in the pul- 
monary artery, and commented upon one or two points in the 
paper. 
Dr LaTHAM thought the condition found post mortem in the 
