omous _Insects_, which I believe to be
the Cause of the Plague, either by mixing it self with the Air and there
destroying them, or else by provoking the Stomach to discharge it self of
those Morbid Juices which would nourish and encourage them.

When I consider that the dead Bodies of the miserable People of
_Marseilles_ were found full of _Insects_, and that those Worms could be
no way so suddenly killed, as by putting Oil or Lemon Juice upon them, it
brings to my Mind several Tryals I have made upon _Insects_ of various
Kinds, in order to occasion their speedy Death. In these Experiments, I
found that most of the larger Kinds would live some Minutes in Spirit of
Wine and other spirituous Liquors, when they were forced into them, and
that Oil immediately suffocated them, from whence I suppose, the Air, or
Breath they draw, is exceeding fine and subtile, and that a thick Air
consists of too gross Parts for them to breath, and that since Oil
destroys the larger Kinds of them immediately, the Oleagenous Particles
evaporating from such Bodies as Oil, Pitch, Tar, _&c._ expanding
themselves, and mixing with the common Air, would render it too thick for
the smaller Kinds to subsist in.

We observe likewise that all _Aromatick Herbs_, &c. were found useful in
the time of the dreadful Pestilence in 1665, which helps to confirm what I
have just now related, for a single Leaf of Rosemary contains at least 500
little Bladders of Oily Juice, which by rubbing, break and afford that
grateful Smell we find in that Plant, but in that as in all other
_Aromatick Herbs_, was we to bruise the Leaves 'till all those Bladders
were broken, the recreating Smell would be lost, and we should find only
remaining an earthy, disagreeable Flavour, arising from the common
undigested Sap; so if we take the Leaves of Fifty several Kinds of
Aromatick Plants, and after bruising them, make up distinctly the bruis'd
Leaves of each into Balls, and dry them by the Sun, or otherwise, they
will all afford the same Smell; for the breaking of those Bladders, or
Blisters, which yield the different Smells (from the Essence they
severally contain) makes them lose all their Spirit or Essence.

In the Culture of these Aromatick Herbs, such as _Rosemary_, _Lavender_,
_Thyme_, &c. we may remark, that they are never destroy'd by any _Insect_,
which may still give us a further Proof of the Antipathy all _Insects_
have to them, for which Reason some People are used to s