"How much does the bat weigh?" demanded Theo, instantly interested.
"About fifteen pounds. It is not very heavy, but the batter wields it with considerable force. After the article has thus been approximately shaped, and the jiggerman has completed it, a mould-runner must carry the freshly modeled piece to the stove-room to be dried; and on his backward trip bring with him two other articles that are already dry. These he takes off the moulds, leaving the dry piece to go to the finisher, and the mould to the batter-out. The fourth man in the team, or crew, is the finisher. His duty is to smooth the rough edges of each article with a damp sponge, or a tool of flat steel. After this process is completed the jiggerman's crew is through with its part of the work and the goods go to the greenroom to be counted, and if perfect accepted by the foreman. Most jiggermen hire their own helpers, as it is simpler for them to do so. Formerly only round articles were made by the jiggermen—such things as cups, plates, bowls, etc. But now oval, as well as round dishes, can be made on a jigger, although elliptical wares are not turned out this way to any very great extent, other processes of shaping being preferred for objects of this type."
"You spoke, Mr. Marwood, of casting some wares," remarked Theo.
The older man smiled.
"You have a good memory, my boy," he said. "I did mention casting. It is an independent process, and shapes of great variety can be fashioned as well as ornamented in this way. By the casting method, too, we are certain of getting articles of uniform thickness. We can even make very thin objects by this means. But the process is destructive of moulds, and therefore has its flaws. The success of the plan is entirely dependent on the mould's absorption of the moisture in the clay; otherwise the method of casting could not be applied to potteries or porcelains. As the clay is compressed the water is squeezed out of it, and this the mould must take up, or the clay would never dry and retain its shape. You can understand that, I think."
"Yes, sir."
"The last of the processes of which I wish to tell you is die-pressing. Here we take a very finely ground clay dust; moisten it a little; and fill a die, or steel mould, with it. This die we then put into a screw, or hydraulic press, and squeeze it under an intense pressure with the result that the piece is shaped very solidly. We use this process for making small, complicated objects such as those employed for electrical purposes. They are brittle and delicate and have to be manufactured with extreme care."
"Are plumbing supplies made this way?"
"No, indeed! Sanitary pieces are too large to be turned out in such a fashion. They are made by hand, being first built up inside enormous moulds. We can employ only the most skilful workmen on this task because the goods are difficult to make. Such a thing as a porcelain bath-tub involves a great deal of clay, and therefore were it to be damaged we should lose much expensive material." Mr. Marwood took out his watch. "Now, there you have all the various ways of shaping clay ware! Its decoration and firing is another story, and far too long a one for us to attack to-day. We must be back at the conservatory at one o'clock for luncheon. Evidently Mr. Croyden got too deeply snowed under to join us, so we shall have to hunt him up. Confess you are hungry."
Theo's eyes twinkled.