f contagious diseases. I have transcribed the particulars from a
letter of Mr. Lightwood of Yoxal, the surgeon who daily attended them, and
at my request, after I had seen them, kept a kind of journal of their
cases.

Miss H. and Miss L. two sisters, the one about four and the other about
three years old, were inoculated Feb. 7, 1791. On the 10th there was a
redness on both arms discernible by a glass. On the 11th their arms were so
much inflamed as to leave no doubt of the infection having taken place. On
the 12th less appearance of inflammation on their arms. In the evening Miss
L. had an eruption, which resembled the measles. On the 12th the eruption
on Miss L. was very full on the face and breast, like the measles, with
considerable fever. It was now known, that the measles were in a farm house
in the neighbourhood. Miss H.'s arm less inflamed than yesterday. On the
14th Miss L.'s fever great, and the eruption universal. The arm appears to
be healed. Miss H.'s arm somewhat redder. They were now put into separate
rooms. On the 15th Miss L.'s arms as yesterday. Eruption continues. Miss
H.'s arms have varied but little. 16th, the eruptions on Miss L. are dying
away, her fever gone. Begins to have a little redness in one arm at the
place of inoculation. Miss H.'s arms get redder, but she has no appearance
of complaint. 20th, Miss L.'s arms have advanced slowly till this day, and
now a few pustules appear. Miss H.'s arm has made little progress from the
16th to this day, and now she has some fever. 21st, Miss L. as yesterday.
Miss H. has much inflammation, and an increase of the red circle on one arm
to the size of half a crown, and had much fever at night, with fetid
breath. 22d, Miss L.'s pustules continue advancing. Miss H.'s inflammation
of her arm and red circle increases. A few red spots appear in different
parts with some degree of fever this morning, 23d. Miss L. has a larger
crop of pustules. Miss H. has small pustules and great inflammation of her
arms, with but one pustule likely to suppurate. After this day they
gradually got well, and the pustules disappeared.

In one of these cases the measles went through their common course with
milder symptoms than usual, and in the other the measly contagion seemed
just sufficient to stop the progress of variolous contagion, but without
itself throwing the constitution into any disorder. At the same time both
the measles and small-pox seem to have been rendered milder. D