94 .. P A T H O 
firft year, the limits may be fixed at 108 and iao. ' For 
the fecond year at 90 and 100. For the third year at 80 
and 108. The fame will very nearly ferve for the fourth, 
fifth, and fixth, years. In the feventh year, the pulfatiohs 
will be fometimes fo few as y^, though generally more.” 
From the twelfth year, then, except that the pulfatioris 
are much more eafily quickened by illnefs or any other 
caufe, they differ but little from thofe of a healthy adult, 
the range of which Dr. Heberden ffates to be from a little 
below 60 to a little above 80 in a minute. From an ave¬ 
rage of five-and-twenty boys, obferved by Floyer, be¬ 
tween the ages of twelve and fixteen, thepulfe was about 
83; in all of them above 80. With regard to the dimi¬ 
nution of pulfe which has been faid to be obfervable in 
the decline of life, Dr. Falconer is difpofed to believe, 
though not very confident in his opinion, “ that the pulfe 
in a healthy perfon becomes gradually flower from about 
forty-five years of age to about fixty, after which period 
it begins again to grow quicker, and to become, as fe- 
veral other circumftances in the fyftem do alfo, more 
refembling that of children. But to this,” he adds, 
there are undoubtedly many exceptions.” 
It has been generally fuppofed that ftature had a great 
influence on the pulfe; and Senac, from obfervations 
made on a hundred men in the royal guards, deduced 
the following eftimate of pulfes in proportion to ftature : 
namely, at two feet, pulfe 90; at four feet, pulfe 80; at 
five feet, pulfe 70 ; and at lix feet, pulfe 60. Dr. Bryan 
Robinfon has likewife made a computation, but it differs 
from Senac’s; and, upon the whole, this point does not 
feem to be fatisfadlorily afcertained. Haller efpecially 
mentions, in oppofition to this opinion, that the Swifs 
people, who are generally tall, have quick pulfes ; and 
further inftances the fafr, that he was himfelf fix feet 
high, and that his own pulfe beat 78 in a minute. 
The pulfe is moreover influenced by the time of day. 
In the morning the pulfe is generally floweft, and be¬ 
comes accelerated towards evening. This is raoft re¬ 
markable in perfons in whom a high degree of nervous 
fenfibility is apparent. The principal caufes which ac¬ 
celerate the pulfe are food, exertion of every kind, (even 
fpeaking or Handing,) warmth, the paftions of hope, joy, 
and anger ; and fometimes, the reaction which fupervenes 
to fudden fhocks and impreffions on the nervous fyftem. 
On the other hand, the pulfe is depreffed by abftinence, 
fleep, fear, anxiety, and grief; and by certain degrees of 
cold. But the operation of all thefe caufes is fubjedt to 
great variation, and is often countera&ed by the influence 
of oppofite agents. 
In feeling the pulfe, the degree of quicknefs is of courfe 
eafily determined by a ftop-watch ; the degree of force 
is eftimated by the refiftance which the artery op’pofes 
when compreffed by the finger. In order to afcertain 
this refiftance, the pulfe fliould be ftrongly comprefied by 
three of the fingers until no pulfation is experienced; 
after which, by gradually relaxing the fingers, we dial 1 
afcertain its proportion with a tolerable accuracy. It is 
to be remarked, however, that the obefity of certain per¬ 
fons alters this circumftance; for not only is it more 
difficult to feel the degree of refiftance of the veffel when 
covered with a thick layer of fat, but fat perfons have 
likewife flower pulfes than lean ones. Another diftinc- 
tion of the pulfe is taken from its hardnefs : this term is 
ufed to imply a peculiar fudden vibration, like the fen- 
fation communicated by the fenfe cord or wire of a mu- 
iical inftrument. “ Some books,” Dr. Heberden remarks, 
“ fpeak of intermitting pulfes as dangerous figns, but I 
think without reafon ; for fuch trivial caufes will occa- 
fion them, that they are not worth regarding in any 
iilnefs, unlefs joined with other bad figns of more mo¬ 
ment. They are not uncommon in health, and are per¬ 
ceived by a peculiar feel at the heart by the perfons 
themfelves every time the pulfe intermits.” We have 
generally ■ onfidered thefe intermitting pulfes as of dyf- 
peptic origin, and havefeen theni removed, in fevers, by 
LOGY. 
a purge. Where the pulfe intermits, and is very unequal 
in its beats, and there is at the fame time palpitation of 
the heart, oppreflion of the breathing, lividity of coun¬ 
tenance, or other ferious fymptoms, then the intermiffion 
is probably one among the figns of fome affedion of the 
heart; but in ordinary cafes, occurring with fymptoms 
of indigeftion, or flight feveriffinefs, it is perfedly void 
of danger. It is curious, indeed, that irregularities of 
the pulfe are fometimes habitual, and difappear only 
with good health. Dr. Heberden fays, “ many perfons 
will likewife have unequal pulfes without any other fign 
of ill health. I have met with two, who, in their bell 
health, always had pulfes very unequal, both in their 
ftrength and the lpaces between them; and, upon their 
growing ill, their pulfes conftantiy became regular; 
and it was a never-failing fign of their recovery, when 
their arteries began again to beat in their ufual ir¬ 
regular manner.” The writer of this article can add to 
thefe, an inftan.ee of an old lady of his acquaintance in 
whom the fame appearances as recorded by Dr. Heberden 
are very ftrikingly marked. 
The propriety of thefe divifions was formerly much 
queftioned, as implying an unneceflary and frivolous de¬ 
gree of minutenefs ; but it feems fcarcely worth while to 
make any remark on this fubjeft, as their neceffity is now 
generally admitted, and is eafily proved by the grand 
criterion of medical theory—its practice. It muft be ad¬ 
mitted, however, after all, that the pulfe, as Celfus fays, 
is “ fallaciffima res and it is only by regarding it in 
conjunction with the other modes of diagnofis that we 
are enabled to make practical ufe ofits various phenomena. 
The circulating fyftem prefents further points of con- 
fideration in regard to morbid changes in the blood. 
Thefe alterations are little underftood. It is probable 
that many exift of great importance, which are neverthe- 
lefs not cognizable to our fenfes. The moft obvious 
change in the blood is that which conftitutes what is 
called Jizy or inflammatory blood. It takes the former 
name from a tough buff-coloured coat which forms on 
its furface after coagulation, and which, according to 
Hewfon, confifts of albumen and a portion of fibrine ; 
and the latter, from its being peculiar for the moft part 
to inflammatory difeafes. Changes of lefs magnitude have 
been obferved in various other difeafes; as a peculiar 
blacknefs in the blood of fcorbutic patients, the want of 
red colour in, and the dilute quality of, the blood in 
fome ftages of dropfical and chlorotic aifeCtion, &c. But 
we forbear to enter into any further notice of this fubjeft 
at prefent. The reader may confult, for more particular 
information on this head, the works of Hewfon, Four- 
croy, and Thackrah. 
The ftate of the ezeernent fyjlem is principally examined 
by analyfis of the excreted lubftances ; as of the urine, 
fweat, uterine difeharge, &c. but in many inftances the 
inveftigation of thefe lubftances is very obfeure. 
The laft fyftem which remains to be noticed as afford¬ 
ing certain information in refpeft to diagnofis, is the 
nervous. The operation of the five fenfes, the elevated 
or depreffed ftate of the Ipirits, the ratiocinative and ima¬ 
ginative functions, afford notice of the degree of danger 
of fome maladies in.a moft certain manner; and hence 
deferve to be ftudied with diligence and attention. 
We now proceed to fpeak of Therapeutics, that 
branch of medicine to which all the other branches Hand in 
relation only as auxiliaries; auxiliaries,it muft be confeffed 
however, the attainment of which is ablolutely neceffary 
ere we can prafitife this branch in a philofophic manner. 
Unfortunately this truth has till lately been unknown. 
The long, the tedious, and (to untutored minds) 
the uninterefting, path of anatomical relearch, of obfer- 
vation, of experiment, and of cautious deduftion, 
fuits not the tafte of mankind in general. Hence they 
have attempted to cure their infirmities by fhorter and 
pleal'anter methods ; and hence, even now, the wonder¬ 
working fpecific claims unmerited attention; and the 
therapeutical 
