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ON THE EARLY STAGES OF INFLAMMATION 
SECTION I 
On the Aggregation of the Corpuscles of the Blood. 
The tendency of the corpuscles of the blood to aggregate together, con- 
stitutes, as we shall see, an important element in the cause of the obstruction 
which they experience in the vessels of an inflamed part. It is therefore desir- 
able that we should be acquainted with the nature of the phenomenon. 
If a drop of human blood just shed is placed between two plates of glass 
and examined with the microscope, the red corpuscles are seen to become applied 
to one another by their flat surfaces, so as to form long cylindrical masses like 
piles of money, as first observed in 1827 by my father and Dr. Hodgkin; and 
the terminal corpuscles of each ‘ rouleau’ adhering to other rouleaux, a network 
is produced with intervals of colourless liquor sanguinis. Rapid movement of 
the blood prevents this occurrence, but it commences as soon as the corpuscles 
approach to a state of quiescence, and I have seen short rouleaux already present 
in a drop drawn from my own finger within ten seconds of its emission. In 
this respect the aggregation of the red corpuscles differs from the coagulation 
of the fibrine, which does not begin till some minutes after withdrawal from 
the vessels. There is, in fact, no connexion whatever between the two processes, 
as is clear from the circumstance that if a drop of blood is stirred with a needle 
while coagulation is taking place, so as to remove the whole of the fibrine, the 
corpuscles, which have been separated from one another by the agitation to 
which they have been subjected, aggregate again in the serum in the same 
manner as they did at first in the liquor sanguinis. The beautifully regular 
form of the long masses of corpuscles has suggested to some persons the idea 
of the operation of some peculiar vital attraction in their formation, while by 
others the aggregation has been supposed due to merely physical causes, but 
has never, I think, received a complete explanation. For my own part, I am 
satisfied that the rouleaux are simply the result of the biconcave form of the 
red discs, together with a certain, though not very great degree of adhesiveness, 
which retains them pretty firmly attached together when in the position most 
favourable for its operation, namely, when the margins of their concave surfaces 
are applied accurately together, but allows them to slip upon one another when 
in any other position. There is never to be seen anything indicating the exis- 
tence of an attractive force drawing the corpuscles towards each other: they 
merely stick together when brought into contact by accidental causes. Their 
adhesiveness does not affect themselves alone, but other substances also, as 
may be seen when blood is in motion in an extremely thin film between two 
