610 
REMARKS ON COMPOSITION OF THE BLOOD. 
obtained. A microscopic examination of solidified albumen 
does not. however, show that in acquiring this condition it 
has assumed any definite or structural form. It is at most 
granular. 
It has already been stated that we possess no other means 
of obtaining serum except from coagulated blood. Nature, 
however, can readily separate it in large quantities from the 
other constituents of the liquor sanguinis. We observe this 
under man} T circumstances, and frequently when an animal 
is in a weak and debilitated condition from disease. It is 
then that the serous part of the blood exudes through the 
capillary vessels and accumulates in the areolar tissue or in 
some of the great cavities of the body. The diseases which 
commonly pass under the term dropsy are especially referable 
to a cause of this kind. These effusions may differ, and 
even considerably so, from pure serum in the proportions 
of albumen and saline matters which they contain ; but never¬ 
theless they are essentially of a serous nature, as is shown by 
their analyzation ; and as such they afford a proof that the 
serum is capable of being expelled from the living vessels 
apart from the other constituents of the blood. 
Salts of the Blood. —The saline matters of the blood 
are various, and are met with in the serum. They consist 
chiefly of the phosphate of lime and magnesia, the tribasic 
phosphate of soda, with the chlorides of sodium and potas¬ 
sium. Besides these,thereare some other salts,which,although 
important in a physiological point of view, need not be 
especially mentioned in a paper of this kind. The phos¬ 
phate of lime exists in considerable proportion, for when 
separated from the blood it is required to give strength and 
solidity to the bones, that they may be enabled to support 
the weight of the animal and resist the force of the muscles 
in the various movements of the frame. 
The Fibrine. —This constituent of the circulating fluid 
may be considered as the basis of nearly all the solids of the 
body. It exists in the blood in a state of perfect solution, 
but possesses the remarkable property of becoming solid 
either within or without the vessels, and whether separated 
or not from the other component parts of the blood, provided 
this fluid becomes stagnant. The coagulation of the blood is 
entirely due to the presence of the fibrine. The power of the 
fibrine to become solid led at one time to its being designated 
“ setf-coagulable lymph,” a name by which it is described bv 
John Hunter, in his great work on f The Blood and Inflam¬ 
mation/ The term fibrine is, however, the more appropriate 
