eries, into greater
energy of action than natural, and thus causes fever with strong pulse;
which, as it was supposed to be most frequently excited by increase of
irritation, is called irritative fever or synocha.

Similar to this in the small pox, which is given by inoculation, the
stomach is affected secondarily, when the fever commences; and hence in
this small-pox the pulsations of the heart and arteries are frequently
stronger than natural, but never weaker, for the reasons above given.
Whereas in that small-pox, which is caused by the stomach being primarily
affected, by the contagious matter being swallowed with the saliva, whether
the tonsils are at the same time affected or not, the pulsations of the
heart and arteries become weak, and the inirritative fever is produced, as
explained above, along with the confluent small-pox. This unfolds the cause
of the mildness of the inoculated small-pox; because in this disease the
stomach is affected secondarily, whereas in the natural small-pox it is
frequently affected primarily by swallowing the contagious matter mixed
with saliva.

In the measles I suppose the contagious matter to be dissolved in the air,
and therefore not liable to be mixed with the saliva; whereas the variolous
matter is probably only diffused in the air, and thence more readily mixed
with the saliva in the mouth during respiration. This difference appears
more probable, as the small-pox I believe is always taken at a less
distance from the diseased person than is necessary to acquire the measles.
The contagion of the measles affects the membranes of the nostrils, and the
secretion of tears in consequence, but never I suspect the stomach
primarily, but always secondarily; whence the pulsation of the heart and
arteries is always stronger than natural, so as to bear the lancet at any
period of the disease.

The great mildness sometimes, and fatality at other times, of the scarlet
fever may depend on the same circumstance; that is, on the stomach being
primarily or secondarily affected by the contagious matter, observing that
the tonsils may be affected at the same time with the stomach. Should this
prove to be the case, which future observations must determine, what
certain advantage must arise from the inoculation of this disease! When it
is received by the skin primarily I suppose no sore throat attends it, nor
fever with weak pulse; when it is received by the stomach primarily, the
tonsils are af