33 
structure of the brain and nerves , &c. 
and diffused through the body, which he termed diffusa, and 
the nerves communicated between them. This grand idea 
of Mr. Hunter's, Mr. Bauer, by his discovery of this trans- 
parent mucus, soluble in water, has realized. 
To complete the investigation of this subject, it only re- 
mained to determine, whether this transparent substance, 
soluble in water, is actually an ingredient in the blood, or is 
formed after the first changes of that fluid into the solids of 
the body have taken place. 
To ascertain this point, two ounces of blood were drawn 
from the arm of a healthy man, and allowed to stand at rest 
till all the serum separated from the coagulum, which required 
36 hours ; the serum was then carefully poured off, and the 
phial filled up with distilled water, and the changes that oc- 
curred were attended to. In 24 hours, the upper parts of 
the coagulum, particularly at the edges, became tumid, appa- 
rently from having imbibed some of the water. This part was 
of a light red colour, and semi-transparent. A small portion 
of it was cut off and put into a saucer with distilled water, 
covered over by a watch glass. In 24 hours, carbonic acid 
gas was seen in bubbles round the edge of the watch-glass, 
the colouring matter had mixed with the water, and the 
whole of the substance was nearly dissolved. 
From this experiment, confirmed by many others, this 
mucus is not only readily discovered in the blood, but proves 
to be the medium by which the colouring matter is attached 
to the surface of the red globules ; and therefore when 
these red globules are put into water, they lose their colour 
from the medium dissolving by which it was attached to 
them. 
MDCCCXXI. 
F 
