STATUARY PORCELAIN. 



surfaces, each part having a sunk impression of one side of the 

 intended object. A clear enough notion of such a mould may be 

 obtained from a common bullet-mould. 



When the two parts of the mould are brought into contact, it 

 will leave within it a hollow space corresponding exactly in form 

 with the intended figure, but having a small opening through 

 which the liquid may be introduced. 



The statuary paste is brought, by mixture with about its own 

 weight of water, to the consistency of a thick cream, and being 

 well and carefully mixed, so as to be quite homogeneous, it is 

 poured into the mould, which is kept full of it for a certain time, 

 more or less according to the thickness which it is desired to give 

 to the statuary material composing the object. While it thus 

 stands, the bibulous quality of the plaster mould causes it to imbibe 

 water from that portion of the creamy liquid or " slip," as it is 

 called, which is in contact with it, so that a coating of paste, in a 

 sufficiently dry state to have coherence, remains attached to the 

 surface of the mould. Within this is contained that portion of 

 the slip which still remains in the liquid state. This being dis- 

 charged through a small hole in the mould, provided for that 

 purpose, the mould remains lined with a solid coating of the por- 

 celain paste of a certain thickness. 



If it be desired to render the coating upon the mould thicker, so 

 as to give greater strength and weight to the object moulded, the 

 process is repeated ; and, in order to equalise the thickness of the 

 deposit, the mould, if it be not too large, is reversed in its position 

 each time that it receives a new charge of slip. 



When the mould, by this process, has received a coating of 

 sufficient thickness it is opened, and the object thus cast taken out 

 of it ; which is easily accomplished, since no adhesion takes place 

 between its surface and that of the mould. 



The thickness of the article thus formed may be varied within 

 practical limits, from that of the egg-shell to the thickness 

 required by objects of the largest attainable dimensions. A 

 beautiful application of this process is practised in the continental 

 factories, by which a thin, delicate article is produced, called 

 egg-shell porcelain. 



When a large figure, or group of figures, is to be produced, the 

 process is more complex. Let us suppose its height in the model 

 to be twenty-four inches. Separate and independent moulds are 

 previously made for various parts of the piece, and in the larger 

 and more complex subjects the number of these sometimes amounts 

 to forty or fifty. 



Supposing the figure or group to measure twenty-four inches in 

 height as moulded, the shrinking that occurs before these casts 



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