To Professor Silliman.
DEAR SIR,
About a year since I made some experiments on the effect of steam on ignited bodies, with a view to learn the theory of the action of the "American water-burner." These experiments were published in an anonymous paper in the North American Review, and have been published in London, without an acknowledgment of their source.
The effect of them concerning bodies is peculiar, and it probably admits of more extensive application to the arts than in the above named instrument alone.
When a jet of steam, issuing from a small aperture, is thrown on burning charcoal, the brightness is increased, if the coal be held at the distance of four or five inches from the pipe through which the steam passes; but if the coal be held nearer it is extinguished, a circular black spot first appears where the steam is thrown on it. The steam in this case does not appear to be decomposed, and the increased brightness of the coal depends probably on a current of atmospheric air, occasioned by the steam. But when a jet of steam, instead of being thrown on a single coal, is made to pass into a charcoal fire, the vividness of the combustion is increased, and the low attenuated flame of coal is enlarged.
When the wick of a common oil lamp is raised, so as to give off large columns of smoke, and a jet of steam is thrown into it, the brightness of the flame is increased, and no smoke is thrown off.
When spirits of turpentine is made to burn on a wick, the light produced is dull and reddish, and a large quantity of thick smoke is given off; but when a jet of steam is thrown into this flame, its brightness is much increased; and when the experiment is carefully performed, the smoke entirely disappears.
When the vapour of spirits of turpentine is made to issue from a small orifice, and inflamed, it burns, and throws off large quantities of smoke; but when a jet of steam is made to unite with the vapour, the smoke entirely disappears. When vapour of spirits of turpentine and of water are made to issue together from the same orifice, and inflamed, no smoke appears. Hence its disappearing, in the above experiment, cannot be supposed to depend on a current of atmospheric air.
When a jet of steam is thrown into the flame of a spirit of wine lamp, or into flames which evolve no smoke or carbonaceous matter, the same effect is produced as by a current of air.
It appears, from these experiments, that in all flames which evolve smoke, steam produces an increased brightness, and a more perfect combustion.
Now, with a very simple apparatus, steam might be introduced into the flames of street lamps, and that kind of lamp which is used in butchers' shops in London, and in all flames which evolve much smoke. The advantage of such an arrangement would be a more perfect combustion, and a greater quantity of light from the same materials. The flame of the lamps, to which steam is applied, might be made to keep the water boiling which supplies the steam.