_Method of Engraving in Relief on the Shell of a new-laid Egg._
Chuse an egg that has a thick shell; wash it well in fresh water; then
dry it very carefully with a linen cloth; this being done, put some
tallow or fat in a silver spoon; then hold it on the fire; when the fat
is melted and very hot, it will serve instead of ink for drawing with
a new pen whatever you like. This being finished, you are to take the
egg by the two ends between two fingers, and then lay it gently in a
tumbler filled with good white wine vinegar; wherein, after remaining
for three hours and an half, the acid of the vinegar will have eaten
enough of the thickness of the shell; and as it cannot have the same
effect on those places that are covered with the fat, all the drawing
will have preserved its thickness, and will form the relief that is
wanted, the operation sought for.
By this means one may draw on an egg a coat of arms, a mosaic piece,
medallion, or any other design whatever.