m weather, and half an hour in the wind. Rain does not affect the
burning of it. These rings are usually arranged in pairs on brackets
with two branches and an upper circle, the whole of iron, and these
brackets are spaced a hundred yards apart.

[Illustration: FIGS. 9 TO 16.--VARIOUS PYROTECHNIC DEVICES.]

[Illustration: FIGS. 17.--ILLUMINATING ROCKET.]

A _tarred fascine_ consists of a small fagot of dry wood, 20 inches in
length by 4 in diameter, covered with the same composition as the preceding
(Fig. 11). Fascines thus prepared burn for about half an hour. They are
placed upright in supports, and these latter are located at intervals of
twenty yards.

The _Lamarre compositions_ are all formed of a combustible substance, such
as boiled oil,[1] of a substance that burns, such as chlorate of potash,
and of various coloring salts.

[Footnote 1: For preparation see page 9304 of SUPPLEMENT.]

The _white composition_ used for charging fire balls and 11/2 inch flambeaux
is formed of 500 parts of powdered chlorate of potash, 1,500 of nitrate of
baryta, 120 of light wood charcoal, and 250 of boiled oil. Another white
composition, used for charging 3/4 inch flambeaux, consists of 1,000 parts of
chlorate of potash, 1,000 of nitrate of baryta, and 175 of boiled oil.

The _red composition_ used for making red flambeaux and percussion signals
consists of 1,800 parts of chlorate of potash, 300 of oxalate of strontia,
300 of carbonate of strontia, 48 of whitewood charcoal, 240 of boiled oil,
6 of oil, and 14 of gum lac.

A red or white _Lamarre flambeau_ consists of a sheet rubber tube filled
with one of the above-named compositions. The lower extremity of this tube
is closed with a cork. When the charging has been effected, the flambeau is
primed by inserting a quickmatch in the composition. This is simply lighted
with a match or a live coal. The composition of the Lamarre quickmatch will
be given hereafter.

A Lamarre flambeau 11/2 inch in diameter and 3 inches in length will burn for
about thirty-five minutes. One of the same length, and 3/4 inch in diameter,
lasts but a quarter of an hour.

A _fire ball_ consists of an open work sack internally strengthened with a
sheet iron shell, and fitted with the Lamarre white composition. After the
charging has been done, the sphere is wound with string, which is made to
adhere by means of tar, and canvas is then wrapped around the whole.
Projectiles of this kind, which have dia