When the velocity of the jet is gradually increased there is a certain range of velocity for which the jet is unstable, so that any deviation from the straight rush-out tends to increase as the jet moves up. If then the jet is just on the point of instability, and is subjected as its base to alternations of motion, the sinuosities impressed on the jet become larger and larger as it flows out, and the flame is as it were folded on itself.
In that condition of affairs the flame of war was kindled between the British and the French in Europe in 1745.
The magnetometric method was employed, and the metals, in the form of ovoids, were heated by a specially designed burner, fed with gas and air under pressure, which directed 90 fine jets of flame upon the asbestos covering the ovoid.
It is probable that when a flame is smoking badly, distinct traces of carbon monoxide are being produced, but when an acetylene flame burns properly the products are as harmless as those of coal gas, and, light for light, less in amount.
It burns with a pale-blue flame forming silicon fluoride, silicofluoric acid and silicic acid.
In the last case it becomes coated with a greyish-black layer of an oxide (dioxide (?)), at a red heat the layer consists of the trioxide (B1203), and is yellow or green in the case of pure bismuth, and violet or blue if impure; at a bright red heat it burns with a bluish flame to the trioxide.
Cadmium salts can be recognized by the brown incrustation which is formed when they are heated on charcoal in the oxidizing flame of the blowpipe; and also by the yellow precipitate formed when sulphuretted hydrogen is passed though their acidified solutions.
Kindle in all hearts the flame of virtue.
Cupping his hands around the flame, he sucked life into the cigarette and then shook the flame from the match before tossing it into an ashtray.
The use of such furnaces has very considerably diminished, owing to the general introduction of coal-gas for heating purposes in laboratories, which has been rendered possible by the invention of the Bunsen burner, in which the mixture of air and gas giving the least luminous but most powerfully heating flame is effected automatically by the effluent gas.