8 Sir Everard Home’ s farther investigation 
this fluid was left a few minutes on the glass, not only many 
new globules were formed, but the original small ones visi- 
bly increased on the field of the microscope, not by several 
globules uniting, but by accession of substance ; and he 
watched several that enlarged to the full size of blood 
globules enclosed in their colouring matter : in that state they 
appeared more opaque ; and when the glass was laid upon 
black paper, they appeared as distinctly to be milk-white, 
as the globules of the blood when the glass is laid upon 
white paper appeared to be bright red. When the fluid is 
diluted with water, no additional globules are produced, and 
the large ones are reduced in size, in the same manner as 
the red globules are, when their colouring matter is dissolved, 
and is leaving them. When there is a sufficient quantity of 
the fluid left to evaporate, ramifications are formed in every 
respect as distinct as those shown in a former Lecture, in the 
magnified drawing of a drop of human blood in the state of 
coagulation. 
From the observations Mr. Bauer has had the opportunity 
of making upon the contents of the lacteal glands, he is satisfied 
that the full sized globules acquire that form in these glands, 
and that afterwards, so far as respects their external appear- 
ance, no change is necessary for their conversion into red 
globules, but their becoming red. 
As the exposure of the blood to the air in its passage 
through the lungs, restores the brilliancy of colour that is 
lost in the circulation through the body, we can have no 
doubt that it is in the vessels of the lungs the blood receives 
its original hue. 
