FIG. 1. - PRODUCTION OF ILLUMINATING GAS.
Burn a piece of paper of about the size of the hand upon a clean porcelain plate, and this will serve to show the phenomena of carbonization and the formation of empyreumatic products under the action of heat. Under the burned paper there will be found a yellowish deposit which sticks to the fingers, and which consists of oil of paper produced by distillation. An idea of the production of illuminating gas through the distillation of coal may be easily given by means a single clay pipe. Upon filling the bowl of this with fragments of coal, closing the opening with clay, and, after the latter is dry, placing the bowl in a coal fire so that the stem shall project, gas will soon be observed issuing from, the latter, and, when lighted, will give a very bright flame. If the pipe seems to be a little too costly, recourse maybe had to a large piece of wrapping paper rolled into the form of a cornucopia, and held in the left hand by means of the pointed end. If, after an aperture has been made in this near the point, the base be lighted, the heat developed by the flame will produce a sort of distillation of the organic matter of the paper, and the empyreumatic and gaseous products will rise in the cone, and make their exit through the orifice, where they may be lighted with a match (Fig. 1). It goes without saying that this experiment lasts but a few seconds; but, as short as this period is, it is sufficient to give a demonstration of the production of illuminating gas through the distillation of organic matters.
Care should be taken not to set anything on fire while performing it, and it is well to operate over a pavement, and far from any inflammable materials.