Tommy, perching himself upon a high stool beside the troughs, regarded his visitors with calm superiority, and was evidently disposed, in this his stronghold, to treat with them _ex cathedra_. "There, thin, Ma'am," began he, "that's what I call iligant ile intirely. Look at it jist!" And taking from its shelf a long tubular glass, he ladled up some of the oil, and held it to the light for inspection. When this had been duly admired, the professor informed his audience that the first product of the still is the gas, which is led off as previously described. Next comes naphtha, benzine, or, as Tommy and his comrades call it, "binzole." This dangerous substance is led from the troughs of the testing-house to a subterraneous tank, the trap-cover of which was subsequently lifted, that the visitors might peep, as into the den of some malignant wild creature. From this it is again drawn, and, mixed with the heavy oil or residuum of the still, is principally used for fuel, as before described. "And how soon do you cut off for oil?" inquired Mr. Williams, carelessly. The fat man gave him a look of solemn indignation, and proceeded without heeding the interruption. "Whin I joodge, Ma'am, that the binzole is nigh run out, I tist it with a hyder-rometer, this a-way." And Tommy, descending from the stool, took from the shelf first a tin pot strongly resembling a shaving-mug, and then a little glass instrument, with a tube divided into sections by numbered lines, and a bulb half filled with quick-silver at the base. Filling the shaving-mug with oil, the lecturer dropped into it his hydrometer, which, after gracefully dancing up and down for a moment, remained stationary. "It's at 55 deg. you'll find it. Look for yersilf, Ma'am," he resumed, with the serene confidence of the prestidigitateur who informs the audience that the missing handkerchief will be found in "that gentleman's pocket." Miselle examined the figures at high-oil mark, and found that they were actually 55 deg.