290 MOULDING AND CASTING. 



face is then lightly oiled over in every part with 

 salad-oil, to prevent the plaster from sticking to 

 the skin. Procure some fresh burnt plaster, and 

 mix it with water to a proper consistence for 

 pouring. Then pour it by spoonfuls quickly all 

 over the face (taking care the eyes are shut), till 

 it is entirely covered to the thickness of a quarter 

 of an inch. This substance will grow sensibly 

 hot, and in a few minutes will be hard. This 

 being taken off will form a mould, in which a 

 head of clay may be moulded, and therein the 

 eyes may be opened, and such other additions 

 and corrections may be made as are necessary. 

 Then, this second face being anointed with oil, 

 a second mould of plaster must be made upon it, 

 consisting of two parts joined lengthwise along 

 the ridge of the nose ; and in this a cast in plas- 

 ter may be taken, which will be exactly like the 

 original. 



To take Casts from Medals. 



In order to take copies of medals, a mould must 

 first be made ; this is generally either of plaster of 

 Paris, or of melted sulphur. 



After having oiled the surface of the medal 

 with a little cotton, or a camel's hair pencil dip- 

 ped in oil of olives, put a hoop of paper round it, 

 standing up above the surface of the thickness you 

 wish the mould to be. Then take some plaster 

 of Paris, mix it with water to the consistence of 

 cream, and with a brush rub it over the surface of 

 the medal, to prevent air-holes from appearing; 

 then immediately afterwards make it to a sufficient 

 thickness, by pouring on more plaster. Let it 



