faces are smooth like this, and as it were quilted, in the same manner. Rue, or Herb-
grafs, is polished, and all over indented or pitted.
The Part that might properly be called the Under side of the Leaf, had a downy Sur-
face, which appeared through the Microscope much like a Thicket of Bushes.
The Leaves and Stalks of most Vegetables are covered with Down or Hair, and there
seems as great a Variety in the Shape, Size, and Growth of these fecundary Plants, (if we
may so term them, being somewhat analagous to the Hairs in Auimals) as there is be-
tween small Shrubs. They consist usually of small transparent Parts, some in the Form
of minute Needles, as on the Tbistle, Cowage, Nettle, &c. Others are like Cats-Claws,
as the Hooks of Clivers, the Beards of Barley, the Edges of several Sorts of Grass,
Reeds, &c. And on many Plants, such as Colts-foot, Rose-Campion, Poplar, Willow,
and all the downy Kinds, they grow in the Form of Bushes, but much diversified in
each particular Plant.
A Multitude of small round Balls, exactly globular, and much resembling Pearls,
were observable amongst the little Bushes or Down, as they are represented, C C C C C,
Infinite Numbers of such as these may be discerned on Sage and several other Plants ;
which was probably the Reason why KIRCHER supposed them covered with Spiders
Eggs, though in truth these are nothing else but a kind of gummy Exsudation, and not
the Eggs of any Insect ; as may be concluded from their being found upon them all the
Year, and scarce changing their Magnitude at all.
D D D represent the irregular Disposition of the downy or bush-like Substance.
PLATE VI. FIG. 3.
THIS Object is a Piece of the finest Lawn, as it appears before the Microscope.
It seems introduced by Mistake into this Plate, and belongs properly to Plate II.
where Ribbon, Taffaty, and Things of its own Kind are examined. A Description of it is
therefore given where that Plate is explained, Page 4, to which we refer the Reader.
An EXPLANATION of the TWELFTH PLATE
A Piece of Stinging Nettle
A Piece of Stinging Nettle, as enlarged by the Microscope, is the Object now before
The whole Surface of the Leaf is set thick with sharp Thorns or Prickles, which are
just visible to the naked Eye ; but when magnified by Glasses, their Form is discoverable
as at A B, A B, &c. Each of these consists of two Parts, different in Shape and Quabry.
The Part A resembles a round Bodkin, tapering from B, till it ends in a very sharp Point.
Its Substance is hard and stiff, exceeding transparent, and hollow from Top to Bottom, as
has been found by many Trials. The lower and thicker Part B, which is as it were the
Basis whereon the Prickle stands, and of a much more pliable Confistence, in Shape re-
sembles a wild Cucumber, and is evidently a little Bladder, or Vessel filled with a limpid
Liquor, always in Readiness to be ejected through the Cavity of the Prickle, when any
thing presses hard upon it.
This Configuration enables us to account for the Effects of what we call the Stinging
of a Nettle ; the Manner of which the Doctor fully discovered by the following curious
Having provided a single Glass, whose Focus was at the Distance of about half an
Inch, fasten'd in a little Frame, that it might be managed easily, he perceived by the
Help thereof, that on thrusting his Finger gently against the Ends of a Nettle's Prickles,
they did not bend in the least ; but he could discern a Liquor rising towards the Points thereof,