Passing through a variety of places in which the trituration, purification, and cleaning of the materials were going on, we mounted to an upper story that reminded us of the yard in which the cunning captain of the Forty Thieves, when he was disguised as an Oil Merchant, stored his pretended merchandise. It was filled with rows and rows of great clay jars, something like barrels with their heads knocked out. Each had, instead of a hoop, an indented band round the middle, for the insertion of the iron gear by which they were, in due time, to be lifted into and out of the raging furnaces. There were two sizes; one about four feet deep, and three feet six inches in diameter, technically called "pots," and destined to receive the materials for their first sweltering. The smaller vessels (_cuvettes_) were of the same shape, but only two feet six inches deep, and two feet in diameter. These were the crucibles in which the vitreous compound was to be fired a second time, ready for casting. These vessels are _built_--for that is really the process; and it requires a twelvemonth to build one, so gradually must it settle and harden, and so slowly must it be pieced together, or the furnace would immediately destroy it--of Stourbridge clay, which is the purest and least silicious yet discovered. "We have now," said Mr. Bossle, wiping his spectacles, and gathering himself up for a loud Johnsonian period, "seen the raw materials ready to be submitted to the action of the fire, and we have also beheld the vessels in which the vitrification is to take place. Let us therefore witness the actual liquefaction." In obedience to this grandiloquent wish, we were shown into the hall of furnaces.