copper. An attempt has been made to cover the
hulls with anti-corrosive paint and cover this with an outside coat
which should resist the attack of barnacles. Somehow the barnacles
eat their way through the paint and attach themselves to the hull. The
vast item of expense attached to the dry-docking of steel ships makes
this matter a not unimportant one. The barnacles interfere greatly
with the speed of a vessel, and in a cruiser speed is of prime
importance. They attach themselves in an incredibly short time to a
steel hull, and it is not long before their effect can be noted by a
comparison of the reading of the log.

How to Frost Glass.--Two ounces of spirits of salts, two ounces of oil
of vitriol, one ounce of sulphate of copper, one ounce of gum arabic,
mixed together and dabbed on with a brush; or this:--Dab your squares
regularly over with putty; when dry go over them again--the imitation
will be executed. Or this:--Mix Epsom salts with porter and apply it
with a brush. Or this one:--Grind and mix white lead in three-fourths
of boiled oil, and one-fourth of spirits of turpentine, and, to give
the mixture a very drying quality, add sufficient quantities of burnt
white vitriol and sugar of lead. The color must be made exceedingly
thin, and put on the panes of glass with a large painting-brush in as
even a manner as possible. When a number of the panes are thus painted
take a dry duster, quite new, dab the ends of the bristles on the
glass in quick succession till you give it a uniform appearance;
repeat this operation till the work appears very soft, and it
will then appear like ground glass. When the windows require fresh
painting, get the old coat off first by using strong pearlash water.

How to Preserve Posts.--Wood can be made to last longer than iron
in the ground, if prepared according to the following recipe:--Take
boiled linseed oil and stir in pulverized coal to the consistency of
paint. Put a coat of this over the timber, and there is not a man that
will live to see it rot.

What Diamond Dyes and Paints Are Made of.--Solutions of the aniline
colors.

What the Ingredients Are of Soapine and Pearline.--They consist of
partly effloresced sal soda mixed with half its weight of soda ash.
Some makers add a little yellow soap, coarsely powdered, to disguise
the appearance, and others a little carbonate of ammonium or borax.

How Many Thousand Feet of Natural Gas are Equal in Heat-Creating Power
to One To