PATHOLOGY. 
refults from “diminifhed fenfibility of the nervous fyf¬ 
tem ; diminifhed adtion of the heart; a contradted ftate 
of the fmall arteries.” The height of it, from “ increafed 
fenfibility of the nervous fyftem; increafed adtion of the 
heart; increafed flow of blood through the fmaller arte¬ 
ries, the oppolition which is made by the exertion of the 
contractile power of thefe vefl'els being overcome by the 
increafed adtion of the .heart.” The decline from “ di- 
ininifhed fenfibility of the nervous fyftem ; enfeebled 
adtion of the heart ; relaxed ftate of the fmall arte¬ 
ries.” 
The refpedtive ftates of the feveral ftages above enume¬ 
rated, Dr. Nicholl confiders, may occur in either of the 
three following orders : “ i. Contradtion of the fmall 
arteries; diminiflied adtion of the heart; torpor of the 
nervous fyftem. 2. Diminifhed adtion of the heart; tor¬ 
por of the nervous fyftem ; contradtion of the fmall arte¬ 
ries. 3. Torpor of the nervous fyftem ; contradtion of 
the fmall arteries ; diminiflied adtion of the heart.” 
Adverting then to the fubfequent phenomena, Dr. 
Nicholl fays, that “ thefe three ftates having exifted an 
uncertain time, a new order of ftates arifes. The adtion 
of the heart becomes increafed, increafed fenfibility of 
of the nervous fyftem takes place, and anlncreafed quan¬ 
tity of blood is received by the fmall arteries. Thefe 
three changes may take place in varied order; for in- 
ftance : the increafed adtion of the heart may firft arife : 
this may produce a removal of the torpor of the nervous 
fyftem; audit may, by increafing the momentum of the 
blood, overcome the refiftance which is offered by the ex¬ 
ertion of the contractile power of the fmall arteries to 
that fluid. Or, the fenfibility of the nervous fyftem may 
become increafed; and to this altered ftate of that fyftem 
may fucceed increafed adtion of the heart, and a more 
copious flow of blood through the fmall arteries. Or, if 
the contradted ftate of the fmall arteries give way, a 
more free and powerful adtion of the heart may follow, 
and the torpor of the nervous fyftem may be removed.” 
The ftates which produce the fymptoms of the fecond 
ftage of fever may, then, occur in either of the three 
following orders, viz. j. Increafed adtion of the heart; 
increafed flow through fmall arteries; increafed fenfibi¬ 
lity of nervous fyftem. 2. Increafed fenfibility of ner¬ 
vous fyftem ; increafed adtion of heart; increafed flow 
through fmall arteries. 3. Diminiflied contradtion of 
fmall arteries ; increafed adtion of heart; increafed fenfi¬ 
bility of nervous fyftem. 
“ Having arrived thus far in our inquiry, let us return 
to the ftates which produce the fymptoms of the firft ftage 
of fever. Let us fuppofe a cafe in which increafed con- 
tradliun of the fmall arteries is the firft eftedt of the pri¬ 
mary caufe of fever. In fuch a cafe, the refiftance of¬ 
fered by thofe arteries to the current of the blood may 
induce an obftrudted ftate of the general round of the 
circulation, whence will enfue a turgid condition of the 
larger arterial and venous trunks, and of the cavities of 
the heart; and from thefe effedts will arife an oppreffed 
and an over-powered ftate of the adtion of the heart. 
The obftrudted ftate of the circulation will lead to a 
turgid ftate of the cerebral blood-veflels ; which eft’edt, 
as well as the want of a free fupply by thofe vefl'els of 
blood which has duly undergone the pulmonic procefs, 
will induce torpor of the cerebral ftrudtures, and, from 
the torpid ftate of thofe ftrudtures, as well as from the 
diminution of the quantity of blood received by the fmall 
arteries, will enfue diminiflied fenfibility of the nerves 
in general. Thus will the feveral caufes of the fymp¬ 
toms of the early Jloge of fever be prefent. 
“ The action of the heart, at firft overpowered by the 
refiftance offered to the blood by the fmall arteries, and 
ftill more enfeebled in confequence of the diminifhed 
fenfibility of the nervous fyftem, may gradually become 
increafed. It may become increafed, poffibly, from its 
myn powers of contradtion having acquired an accumu¬ 
lation of energy during its opprefl’ed ftate, or in confe¬ 
quence of increafed fenfibility of the nervous fyftem ; or 
VOL. XIX. No. 1297. 
perhaps, in fome inftances, owing to a diminution of the 
contradtion of the fmall arteries, and a confequent dimi¬ 
nution of oppolition to the adtion of the heart. Should 
the adlion of the heart become increafed, the momentum 
of the blood will be increafed, and confequently the 
refiftance offered by the fmall arteries may be borne down ; 
in which cafe the freedom of the circulation will be re- 
flored. The removal of the obftrudled ftate of the cir¬ 
culation, and the diilribution of an increafed quantity 
of blood throughout the nervous fyftem in general, will 
remove the caufes of torpor of that fyftem. Torpor of 
the cranial brain is, in many inftances, fucceeded by a 
degree of fenfibility of that ftrudlure greater even than 
that which immediately preceded the infenfible ftate of 
it. This is conftantly the cafe after fleep. So alfo an in¬ 
fenfible ftate of the nerves in general is, in many in¬ 
ftances, fucceeded by a degree of fenfibility greater than 
that which immediately preceded the infenfible ftate. In 
the cafe under conlideration, then, it may happen that 
the torpor which prevailed in the early ftage of fever 
may, after it has exifted for fome time, gradually be re- 
folved into a ftate of increafed fenfibility. The prefence 
of increafed fenfibility of the nervous fyftem will be 
followed by increafed adlion of the heart, and by the 
flow of an increafed quantity of blood through the 
fmall arteries. Thus may thofe ftates be formed which 
give rife to the fymptoms attendant on the fecond Jloge 
of fever. 
“Suppofe that torpor of the cerebral ftrudlure is the 
firft effedt of the primary caufe of fever. Such-a ftate will 
give rife to general in fenfibility. The adlion of the heart 
will be diminifhed, and the contradtion of the fmallarteries 
will be increafed. The increafed contradtion of thefe 
arteries will, as we have feen, tend to produce an en¬ 
feebled adtion of the heart; and a diminution of the ac¬ 
tion of the heart leads, as we have alfo feen, to increafed 
contradtion of the fmall arteries. Thus may the caufes 
of thofe fymptoms which attend the early ftage of fever 
he prefent. 
“ If the torpor of the cerebral ftrudtures, after it has 
exifted for an uncertain time, fubfides, and is fucceeded 
by a degree of fenfibility even greater in degree than that 
which preceded it, fuch new condition of the cerebral 
ftrudtures will be attended by increafed fenfibility through¬ 
out the nervous fyftem generally : increafed quantity of 
blood will flow through the fmall arteries. Thus thofe 
ftates will he eftablilhed which give rife to the fymptoms 
attendant on the fecond ftage of fever. 
“ If diminifhed adtion of the heart be the firft 
effect of the caufe of fever, diminution of the momen¬ 
tum of the blood will enfue, to which will fucceed 
increafed contradtion of the fmall arteries and tor¬ 
por of the cerebral ftrudtures, and confequently, a ge¬ 
neral diminution of the fenfibility of the nervous fyftem. 
And thus thofe ftates will be formed which produce the 
fymptoms of the early ftage of fever. 
“ When thefe ftates have exifted an uncertain time, if, 
as we have fuppofed, the heart be enabled, from changes 
which take place within itfelf during its ftate of inadti- 
vity, to adl with a degree of force even greater than be¬ 
fore; the momentum of the blood will be increafed, and 
the refiftance of the fmaller arteries will be overcome 
The torpor of the cerebral ftrudtures will be removed, 
and a preternatural degree of fenfibility of thofe ftruc- 
tures may arife, not only as a confequence of an in¬ 
creafed flow of blood through their blood-veflels, but 
poffibly, as we have fuppofed, as a confequence of the 
previous ftate of torpor. The increafed fenfibility of the 
cerebral ftrudtures will induce a general increafe of fen¬ 
fibility throughout the nervous fyftem, and will caufe 
the action of the heart to be ftill more forcibly exerted. 
Thus, in various ways, thofe feveral ftates which charac¬ 
terize the fecond ftage of fever will be eftablilhed. Du¬ 
ring the exiftence of the fecond ftage of fever, although 
an increafed quantity of-blood flows through the-fmall 
arteries, yet this increafed flow appears to arife, in the 
3 F generality 
