Magnesium lights fitted up to fire with a trip line have been successfully used for obtaining photographs of big game in their native surroundings at night.

Smoke pyrotechnically produced has for several years been used for the testing of drains, and recently successful experiments have been carried out establishing the value of smoke as a protection for fruit blossom against frost.

It has also been used as an insecticide for use against various kinds of parasites; a poisonous smoke has been found of great use in the dislodging and exterminating of rats.

Another agricultural use of pyrotechnic, or in this case perhaps more correctly explosive composition, is the use of explosive cartridges for ploughing; that is, cartridges are exploded at a certain depth in the ground, the effect being to break up the subsoil. The explosive used is a mild and cheap form of dynamite.

The use of rockets and other explosive fireworks for producing rain has been much discussed recently. Many writers deny the possibility of success by such means. There cannot be the slightest doubt, however, that given clouds in the right condition and altitude it is quite possible to cause rain. The writer has seen it done, not once but many times; generally it must be admitted when the rain was not wanted. Maroons fired in wide-mouthed mortars have been used on the Continent for some years to break up hail clouds and bring them down in the form of rain over the vineyards, where a hail storm is a serious calamity to the wine grower.

The use of pyrotechnic signals in connection with aerial travel is gradually increasing. The stores used are practically those evolved and adopted during the great war, modified in some cases to suit peace time requirements, but substantially they are those described in the chapter on Military Pyrotechny.

LIST OF THE PRINCIPAL INGREDIENTS USED IN
PYROTECHNY AT THE PRESENT TIME.

Force and Sparks Compositions.