THE TECHNOLOGIST. [May 1, 1861 



468 A VISIT TO THE WOKKS OF 



We now enter the potter's room, where the crucibles are fashioned. 

 This room might be a part of any large pottery were it not for the 

 funereal hue of everything around. On each side are ranged the lathes 

 or wheels, all driven by steam-power, but resembling in other respects 

 the potter's wheel of the earliest ages. Let us watch the growth of one 

 large crucible. The " thrower" takes the necessary quantity of" metal" 

 and submits it to the operation of " wedging," which consists in tear- 

 ing or cutting it into two pieces, and striking them together again 

 with great force. This he repeats until the metal becomes perfectly 

 tractable. He then dashes the mass upon the revolving disc of his lathe, 

 and presses it with his wet hands till it assumes an irregular conical 

 form. He then makes it take a variety of forms, with the object of 

 getting rid of all air bubbles. It is impossible to follow the mass 

 through its numerous changes, but suddenly, when we least expect it, 

 it takes the shape of the crucible. This shape is very rude at first, 

 but under the skilful hands of the thrower it soon becomes beautifully 

 symmetrical. A wire guide is fixed at a certain height above, and at a 

 certain distance from, the revolving mass, and to this the thrower gradu- 

 ally brings the edge of the crucible. With this simple guide he can 

 make a dozen pots resembling each other so perfectly in shape and size, 

 that the most experienced eye can hardly detect any variation in them. 

 The skittle pots are made in precisely the same way, but are contracted 

 at the mouth, after the inside has been properly shaped. Many of the 

 fire-resisting goods manufactured by the Company are shaped by moulds, 

 or by the aid of modelling tools. One of these miscellaneous articles 

 which we see in course of construction is a large bath, five feet long by 

 a foot and a half wide, intended to hold molten zinc. This we are told 

 is for a French order. 



We now follow the pots to the drying-room. Through the centre of 

 this room the upper part of one of the kilns passes, and the heat which 

 would otherwise be wasted is thus applied to a useful purpose. Here 

 we find regiments of pots undergoing the drying process. Many of 

 them have the graceful form of the once-celebrated Picardy pots, and 

 are intended for the French mints. Though unbaked, each article that 

 has remained sufficiently long in the room gives a clear metallic ring 

 when struck. 



The kilns are large conical chambers like those of ordinary pot- 

 teries. The goods to be " fired " are packed in cylindrical cases of fire- 

 clay called " seggars," and these are piled one above the other in the 

 kiln like the basaltic columns of Staffa, and are luted closely together. 

 These seggars protect the goods from the action of the air, which at a 

 high temperature would have the effect of whitening their external 

 surfaces, and so rendering them unsightly. We have the good fortune 

 to be present as the workmen are engaged in emptying a kiln. -We see 

 that the crucibles come from their fire-clay cases exactly as they are 

 sent out from the works. The absurd practice of giving plumbago 



