INGENUITY AND LUXURY 



the substance to be blunged being thrown into wooden 

 tanks, the right proportion of water added, and the 

 mixing done with wooden paddles, hoes, or rakes. 

 In up-to-date potteries, however, mechanical blungers 

 are now used. These are octagonal tanks, in which 

 several propeller-like blades are arranged to revolve 

 horizontally, on the principle of the Archimedean 

 screw, so that the liquid in the tank is kept constantly 

 circulating in all directions, drawn upward and later- 

 ally by the action of the blades, and descending by 

 the action of gravity. The octagonal sides of the 

 blunger help in the mixing process, the particles being 

 jostled against the angles, whereas in a circular tank 

 they might be carried round and round. 



In large factories there is at least one blunger for 

 every one of the several materials to be used in making 

 the body. When these materials have all been brought 

 to the proper density and churned until the mix- 

 ture is uniform throughout, they are passed on to the 

 mixing " arks." The mixing arks are made on the same 

 general principles as the blungers, although they 

 differ somewhat in the details of construction. For 

 convenience they are frequently placed on a lower 

 level than the blungers, and into them the blunged 

 material is pumped, or run, passing through one or 

 more sieves which arrest all lumps, or particles of 

 foreign material. 



There are many ways of measuring the exact pro- 

 portions of the blunged materials that are to go into 

 the mixing ark, such as weighing, or measuring in 

 pails or dippers of a certain size. But as all these 



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