2 Sir Everard Home’s farther investigation 
act of coagulation, evolves aeriform matter, so as to pervade 
the coagulum in every direction ; and that such currents, 
passing through the serum, form permanent tubes, which 
are immediately afterwards filled with red blood, when the 
circumstances in which the coagulum is placed, admit of 
their being so. 
In the present Lecture, I trust that I am enabled to make 
out the greater number, if not the whole, of the component 
parts of the blood. 
My former experiments were made upon coagula recently 
formed from the blood, whether out of the body, or in 
the interstices of parts possessed of life. - Upon the present 
occasion, I have taken an opposite course, and have examined 
the coagula formed in aneurismal tumors. It is to be under- 
stood, that in this disease of the arteries, the coats at the 
part diseased, yield to the impulse of the heart, and admit of. 
being permanently dilated, so as to form a pouch, in which 
the blood that remains at rest, coagulates. This dilatation is 
gradual ; and as the pouch enlarges, the coagulum is found 
to be made up of a succession of layers, affording an opportu- 
nity of observing the changes coagulated blood undergoes 
under such circumstances at different periods of time. 
In the examination of the section of an aneurismal tumor 
in the microscope, Mr. Bauer found that the la}’ , er of the 
coagulum, in contact with the blood in circulation, was red 
in its colour, loose in its texture, and principally consisted of 
red globules from which the colour had been discharged, and 
remained diffused through the mass. Besides these glo- 
bules, he saw others of a smaller size, which he had never 
met with in fluid blood, however frequently he had examined 
