r, 4 drachms; nitric acid, 1 drop; oil of
geranium, 1 drop.

GLASS.--To cut glass, hold it under water, and use a pair of shears.

To make a hole through glass, place a circle of moist earth on the
glass, and form a hole in this the diameter wanted for the hole, and in
this hole pour molten lead, and the part touched by the lead will fall
out.

To Frost Glass. Cover it with a mixture of 6 ounces of magnesium
sulphate, 2 ounces of dextrine, and 20 ounces of water. This produces a
fine effect.

To imitate ground glass, use a composition of sandarac, 2-1/2 ounces;
mastic, 1/2 ounce; ether, 24 ounces; and benzine, 16 ounces.

IRON AND STEEL.--How to distinguish them. Wash the metal and put it into
a solution of bichromate of potash to which has been added a small
amount of sulphuric acid. In a minute or so take out the metal, wash and
wipe it. Soft steel and cast iron will have the appearance of an
ash-gray tint; tempered steels will be black; and puddled or refined
irons will be nearly white and have a metallic reflection.

To Harden Iron or Steel. If wrought iron, put in the charge 20 parts, by
weight, of common salt, 2 parts of potassium cyanide, .3 part of
potassium bichromate, .15 part of broken glass.

To harden cast iron, there should be added to the charge the following:
To 60 parts of water, add 2-1/2 parts of vinegar, 3 parts of common
salt, and .25 part of hydrochloric acid.

To soften castings: Heat them to a high temperature and cover them with
fine coal dust and allow to cool gradually.

LACQUERS.--For Aluminum. Dissolve 100 parts of gum lac in 300 parts of
ammonia and heat for an hour moderately in a water bath. The aluminum
must be well cleaned before applying. Heat the aluminum plate
afterwards.

For Brass. Make a compound as follows; Annatto, 1/4 ounce; saffro, 1/4
ounce; turmeric, 1 ounce; seed lac, 3 ounces; and alcohol, 1 pint. Allow
the mixture to stand for three days, then strain in the vessel which
contains the seed lac, and allow to stand until all is dissolved.

For Copper. Heat fine, thickly liquid amber varnish so it can be readily
applied to the copper, and this is allowed to dry. Then heat the coated
object until it commences to smoke and turn brown.

LUBRICANTS.--Heavy machinery oils. Use paraffine, 8 pounds; palm oil, 20
pounds; and oleonaptha, 12 pounds. Dissolve the paraffine in the
oleonaptha at a temperature of 160 degrees and then stir in the palm oil
a little at a time.