28 REVIEW— THE MICROSCOPIC ANATOMY OF 
cases dies hard. On the contrary, in disorders of a chronic, pas- 
sive, or asthenic character, in all of which there is a deficiency of 
the vital powers, as in typhus, anemia, chlorosis, the blood passes 
to a solid state in a much shorter period than ordinary. In these 
cases the vitality of the blood is very feeble, and it may be said 
to die easily. A remarkable difference is likewise observable in 
the characters of the clot formed in the two classes of disorders 
named : in the first it is firm and well defined ; in the second, soft 
and diffluent.” 
In horses the blood exhibits the buffy coat in a state of health, 
and at no period more markedly than at a time when their health 
or condition is at the highest pitch. This is quite in accordance 
with the “ sthenic” diathesis, though not altogether with the “in- 
flammatory” or “ febrile” state of system. For neither in inflam- 
mation nor in fever is the buffy coat of horses’ blood increased ; 
rather, in general, diminished. After all, however, the buffy phe- 
nomenon is very transient — alterable or destructible by any un- 
usual exertion of body. Mr. Percivall, from a horse “ to every 
appearance in perfect health,” drew a pint of blood ; then had the 
animal galloped for twenty minutes until he “ sweated profusely,” 
and, at the time he was panting from his exertion, drew another 
pint, by unpinning the orifice in the vein made in the first instance. 
“ The coagulum of the first parcel of blood proved sizy, tough, con- 
tracted, and deeply cupped ; that of the latter exhibited no sign 
whatever of buff, was extremely loose and flabby in its texture, so 
that, when handled, it readily mingled with the serum, and in a 
much shorter time than the first parcel went into the putrefactive 
state*.” 
Most interesting accounts follow, of the form, size, structure, 
colour, and uses of the red globules, blood corpuscules, or blood 
discs, as they are now with more propriety designated; which are 
not tiresomely lengthy or speculative, and yet sufficiently so to 
afford every required information. The “ corpuscular theory of 
respiration” is altogether very complete and beautiful. 
From the red discs Mr. Hasssall passes to the consideration of 
the “ white globules” of the blood ; “ far less numerous,” and differ- 
ing from the red “ in size, colour, form, structure, in their proper- 
ties, and doubtless in their usesf.” “The uses of the white cor- 
puscules have not been fully determined : enough, however, of 
their nature has been ascertained to shew that they are closely 
connected with the functions of nutrition and secretion .” 
* Percivall’s “ Anatomy of the Horse,” p. 171. 
-f- Spallanzani was the first to notice the existence of two forms of globules 
in the blood of salamanders ; Muller verified their presence in that of the 
frog, and M. Maudt detected them in man and mammalia. 
