THE BLOOD. 
489 
€ - * ' i » * . . ' 
BUFFY COAT—CUPPED BLOOD. 
I make the consideration of these points a distinct one, because 
I feel desirous to correct what I conceive to be an important error 
practitioners have fallen into. 
Let the crassamentum be examined at the side, and the upper 
layer of it will be found to be yellow or buff-coloured ; below 
this, it will appear of a light red hue ; lower still, darker and 
darker until it becomes a black or dark purple. This is the 
natural or healthy aspect of horses’ blood: but, human blood is 
said never to put on such an appearance but as symptomatic of 
inflammatory, or, at all events, of increased vascular action. 
Whether it does or not, the simple explanation of this phenomenon 
is, that, in consequence of the blood taking an unusually long¬ 
time to coagulate, the red particles, being specifically heavier 
than the fluid containing them, gradually subside to the bottom 
until they are arrested by the process of coagulation. And con¬ 
sequently, as the horse's blood takes so much longer to coagulate 
than the human , it cannot afford any matter for surprise that his 
blood should be always buffy. Still obvious and easily account¬ 
able for as this fact is, buffy blood has been attributed to the 
horse as a mark of disease . 
And so, in like manner, has cupped blood ; by which is meant 
crassamentum, whose upper surface, instead of being flat or per¬ 
fectly plane, is concave or cupped , having its surrounding margin 
elevated and more or less inverted, in the form of a tea-saucer. 
But this is an appearance often to be met with in perfect health: 
one that no more certainly indicates any morbid condition with 
which I am acquainted than does buffy blood. I had a re¬ 
markable instance of this while engaged in some experiments 
connected with this subject. A horse, to every appearance in 
perfect health, was bled to one pound ; after which he was gal¬ 
loped (for the space of about twenty minutes) until he sweated 
profusely: while under extreme agitation from the exertions 
he had been put to, another pint of blood was drawn by un¬ 
pinning the same orifice. The coagulum of the first parcel of 
blood was sizy, tough, contracted, and deeply cupped ; that of 
the last exhibited no signs whatever of buff, was extremely loose 
and flabby in its texture; so that, on being handled, it readily 
mingled with the serum, and in a much shorter time than the first 
went into the putrefactive state. 
This latter fact is intimately connected with what we have 
already advanced regarding the non-coagulation of the blood 
after an animal has been coursed to death ; since, had exertion 
been continued until the horse sunk under it, the blood would 
VOL. IV. 3 x 
