Scientific American/Series 1/Volume 1/Issue 1/A Smoke Filter for Locomotives

A Smoke Filter for Locomotives.—An invention, which promises to be one of great utility, has been recently made by Mr. J. P. Dempfil, a French gentleman, of much scientific talent.—The invention consists of "an attachment" to the chimney of a locomotive, dividing it by a partition in two parts or passages, upward and downward, with a flywheel at the bottom of the downward draft, and a layer of gravel or sand underneath the wheel. The top of the chimney is closed, and the smoke and cinders pass upward through one passage to the top, then descending through the other, (a strong draught being made by the revolution of the flywheel, which is put in motion by the steam,) and all the refuse of the smoke pipe is retained by the grand filter, and the heated air again passes into the furnaces.