bbles of
inflamed phosphoretted hydrogen gas will quickly cover the whole
surface of the fluid in succession, forming a real fountain of fire.

_To take Impressions of Coins, Medals, &c._

Cut fish-glue, or isinglass, into small pieces, immerse it in clear
water, and set it on a slow fire; when gradually dissolved, let it
boil slowly, stirring it with a wooden spoon, and taking off the scum.
The liquor being sufficiently adhesive, take it off the fire, let it
cool a little, and then pour it on the medal or coin you wish to copy,
having first rubbed the coin over with oil. Let the composition lay
about the thickness of a crown-piece on the medal. Then set it in a
moderate air, neither too hot nor too cold, and let it cool and dry.
When it is dry, it will loosen itself; you will find the impression
correct, and the finest strokes expressed with the greatest accuracy.

You may give a most pleasing effect to the composition, by mixing any
colour with it, red, yellow, blue, green, &c., and if you add a little
parchment size to it, it will make it harder and better. This size is
made by gently simmering the cuttings of clear white parchment in a
pipkin, with a little water, till it becomes adhesive.

_To tell a Person any Number he may privately fix on._

When the person has fixed on a number, bid him double it and add four
to that doubling; then multiply the whole by 5; to the product let him
add 12, and multiply the amount by 10. From the total of all this, let
him deduct 320, and tell you the remainder; from which, if you cut off
the two last figures, the number that remains will be what he fixed
upon. For instance,

Suppose the number chosen is 7
Which doubled 14
Add 4 to it, and it will make 18
Multiply 18 by 5, gives 90
To which add 12, is 102
Multiply that by 10, makes 1020
From which deducting 320, the remainder is 700
And by striking off the two ciphers, it becomes
the number thought on 7

_To tell any Number a Person has fixed on, without asking him any
Questions._

You tell the person to choose any number from 1 to 15; he is to add 1
to that number, and triple the amount. Then,

1. He is to take the half of that triple, and triple that half.
2. To take the half of the last triple, and tripl