if one is obliged to be much exposed to the sun, to an
excessively severe malady.

'The curious dependence of the disease on the season of the year
suggested to me the thought that organisms might be the origin of the
mischief. In examining the secretion I regularly found, in the last
five years, certain vibrio-like bodies in it, which _at other times I
could not observe_ in my nasal secretion... They are very
small, and can only be recognised with the immersion-lens of a very
good Hartnack's microscope. It is characteristic of the common
isolated single joints that they contain four nuclei in a row, of
which two pairs are more closely united. The length of the joints is
0.004 millimetre. Upon the warm objective-stage they move with
moderate activity, partly in, mere vibration, partly shooting
backwards and forwards in the direction of their long axis; in lower
temperatures they are very inactive. Occasionally one finds them
arranged in rows upon each other, or in branching series. Observed
some days in the moist chamber, they vegetated again, and appeared
somewhat larger and more conspicuous than immediately after their
excretion. It is to be noticed that only that kind of secretion
contains them which is expelled by violent sneezings; that which drops
slowly does not contain any. They stick tenaciously enough in the
lower cavities and recesses of the nose.

'When I saw your first notice respecting the poisonous action of
quinine upon infusoria, I determined at once to make an experiment
with that substance, thinking that these vibrionic bodies, even if
they did not cause the whole illness, still could render it much more
unpleasant through their movements and the decompositions caused by
them. For that reason I made a neutral solution of sulphate of
quinine, which did not contain much of the salt (1.800), but still was
effective enough, and caused moderate irritation on the mucus
membrane of the nose. I then lay flat on my back, keeping my head
very low, and poured with a pipette about four cubic centimetres into
both nostrils. Then I turned my head about in order to let the liquid
flow in all directions.

'The desired effect was obtained immediately, and remained for some
hours; I could expose myself to the sun without fits of sneezing and
the other disagreeable symptoms coming on. It was sufficient to
repeat the treatment three times a day, even under the most
unfavourable circumstances, in order to