nation of volatile alkali with silver. Gunpowder, or fulminating
gold, are not to be compared with this invention, and the great danger
attending its manufacture prevents us from giving a methodical account
of its preparation to our readers, particularly as it can be
purchased, properly prepared, of the chemists.

The slightest agitation or friction is sufficient to cause its
explosion. When it is once obtained, it can no longer be touched with
safety. The falling of a few atoms of it, from a small height,
produces an explosion; a drop of water falling on it has the same
effect. No attempt, therefore, can be made to enclose it in a bottle,
but it must be let alone in the capsule, wherein, by evaporation, it
obtains this terrible property. To make this experiment with safety,
no greater quantity than a grain of silver should be used; the last
process of drying should be made in a metallic vessel, and the face of
the operator defended by a mask with strong glass eyes.

_To make the Phosphorus Match Bottles._

Nothing more is necessary for this purpose, than to drop small pieces
of dry phosphorus into a common phial; gently heat it till it melts;
and then turn the bottle round, that it may adhere to the sides. The
phial should be closely corked; and when used, a common brimstone
match is to be introduced, and rubbed against the sides of the phial:
this inflames the match when it is brought out of the bottle. Though
there is no danger in phosphorus, till friction, or fire, is applied,
yet persons cannot be too cautious in the use of it, as instances have
been known of one of these bottles catching fire in the pocket, and
very much endangering the person who carried it; likewise, if
carelessly used, small particles are apt to get under the nails, or on
the hand; and if, by accident, they are held to the fire, or rubbed
together, a flame will presently kindle.

_To make a Ring suspend by a Thread, after the Thread has been
burned._

Soak a piece of thread in urine, or common salt and water. Tie it to a
ring, not larger than a wedding-ring. When you apply the flame of a
candle to it, it will burn to ashes, but yet sustain the ring.

_To form Figures in relief on an Egg._

Design on the shell any figure or ornament you please, with melted
tallow, or any other fat oily substance; then immerse the egg into
very strong vinegar, and let it remain till the acid has corroded that
part of the shell which is not covered w