tion was so slow, that t 
744 
«* In some cases the progress of the affec- 
1e pock on the eighth 
day had the common appearance of that of 
the fourth, and that of the sixteenth was like 
_ the usual one on the eighth or tenth. We 
have been shewn a case in which no signs 
appeared of the infection having taken place 
for five weeks ; but in six days, after a second 
inoculation, a pock appeared, and alike from 
both inoculations. 
‘© In twoor three rare instances, an irregu- 
Jar figured pock, followed by a yellow rough 
large irregular figured scab, was produced on 
repeated inoculation; vet the subject could 
not take the small-pox subsequently. 
«© In one case a large niutberry-like pock 
oaly was excited, ¥ei the susceptibility of the 
small-pox was destroyed by it. 
« In no case was the susceptibility of the 
cow-pock, and of course of the smal]-pox, 
destroyed, when'the pimple or pock exeited, 
disappeared within ten of ‘twelve days, al- 
though the inflammation was seen on the 
day afier inoculation, and! when also ‘no cica- 
trix was left behind. + . 
«© The areola is neither.essential im the 
same, nor different constitutions; nor con- 
nected with the fever; nor with the age of 
the matter; nor with the quantity of it ; nor 
with the mode of inoculation ; but with ap- 
parently the state of the skin, in ever difle- 
rent arms of the same person, one arm lad 
borne.a pock with a large red areola, and the 
other had a.pock with nare atall5 some have 
had no areola, and yet a fever; and, others 
no observable feyey, yet there was a consider- 
able areola.” 
The reader will see from the above 
passage, that the authors make the test 
of sufficient vaccination to be, not the 
presence of the areola, nor even the form 
of the vesicle, but simply the time of its 
duration. This opinion indeed is not ex- 
pressed absolutely, and refers chiefly to 
the individual cases'on which it is found- 
ed; but experience would have justified 
2 caution, not to) rely iraplicitly on this 
test alone; as positive evidence might be 
brought of its insecurity. 
The intervention of many of the dis- 
eases in every stage of vaccination, and 
of the small-pox in its earlier progress, 
is explained and illustrated’in a very sa- 
tisfactory manner. © 
We shall transcribe the whole of the - 
twelfth propesition, with the subjoined 
remarks, as they relate to a point of prac- 
tice which has been more controverted 
than any other: 
* 
* No difference equld be perceived in the 
agency of the yaccine matter, according to 
the age of the pock, or to the presence.or ab- 
sence of areola, except iu certain early ages 
ef it being more efficacious than others, - 
_not yet in the scabbing stage, or was but just 
MEDICINE, SURGERY, ANATOMY, &c. 
“« It was the usage of the institution-al-» 
most always to inoculate with matters of the. 
eighth, or eleventh and twelfih days; and _ 
from our ample experience we affirm, that if. 
the pock of the eleventh or twelfth day was — 
beginning, the matter was equally efficacious 
with that of the eighth day; vet, if the pock 
had begun to seab, or was advanced to that 
state, this old matter oftener failed than 
younger matter; but when the matter of such 
old pocks failed to excite the vaecina, const- 
derable inflammation or phlegmonous erup- 
tion or pimple (whichis iniproperty called spu- 
rious cow-pock), did not more frequently oc- 
curthan from younger matter of the distinct 
cow-pock, when it failed, and: the bad conse- 
quences did not ensue more frequently from 
such old matter, than from matter of the 
eighth day, or earlier. ; 
« Whether the matter was taken from a . 
pock which had an arecla or not, the effect 
was not on thataccount different. Wehave 
used matter when it could be had, as early as 
the fifth day, but it cxcited the vaccina with 
the usual appearances; and certainly it was” 
not on account of the,age of the matter more 
mild, sdb 
«« Matter from a pock still containing 
Jymph, though as Jate as the fifteenth, day ; 
and even pus, when the vesicle had become 
a pustnile, generally produced no effect at all 
except like that of a common seraich; but 
sometimes ittook effect, and then it produced 
the genuine distinet vaccina. ’ 
«« In the same arms, matter of the eighth 
day and of the twelfth bas been employed, 
and the eyent was, that each sort excited the 
genuine and similar vaccine pocks; and the 
same efiects were secn from matter, so Ino- 
culated, of the eleventh and fifteenth days.” 
It is a curious question to determine 
the effect of diluting the virus. * The re- . 
porters mixed the matter of asingle pus- 
tule with a quarter cf an ounce measure 
of warm waiér, and produced the pérfect 
disease by subsequent inoculation with 
this diluted virus. We should think the 
proportion of dilution might be full an 
hundred fold in this instance. 
An appendix is added to these elemen- 
tary propositions, containing further il- ' 
lustrations derived from the practice of 
the institution, and abounding with acute 
observation; and the whole concludes 
with documents on the mortality of 
small-pox, and miscellaneous papers re- 
lative to the plan of the institetion. Two 
beautiful coloured plates are prefixed, 
containing several views of the vaccine 
pustule; of some of its anomalies, and of 
the genuine smail-pox pustule, 
This publication merits every atten: 
tion; though concise, it abounds with 
jastruction, and the observations are often 
