Page:The Strand Magazine (Volume 3).djvu/579

 has to be taken to keep the model moist as before, and to see that nothing damages its surface. Each evening it is carefully wetted with the syringe, and covered up with moist cloths.

When the mould has been completed, the next operation is to take it apart piece by piece, or so much of it as will enable the clay model (together with the iron framework), which is no longer of any use, to be removed. If the mould has been well constructed, this is no very difficult matter. The syringe is again brought into requisition, and when the water has penetrated the joints of the separate pieces of the mould it moistens the film of clay deposited by the washing with clay water, and so allows the section to be prized out of its place with comparative ease. When the model has been sufficiently bared to permit of its being worked out that operation is begun.

When this is done we have before us the hollow mould in which the plaster cast has to be made. But, before proceeding with the cast, it is necessary to re-shape and insert the irons (or many of them) which formed the skeleton of the model. These are necessary for the support and strengthening of the group. The irons are further strengthened by wooden struts as the work proceeds. But before anything else is done the various pieces of the mould are carefully washed, so that no particle of the clay of the model remains. They are then given a thin coating of soft soap, and when that is dry they are slightly oiled, so that the plaster of the cast may not adhere.

The process of making the cast then proceeds. The moulder is supplied with bowls of liquid plaster, which he flings upon the inside of the mould with his hand. When he has thus put on a first thin coating he takes lumps of tow, dips them in the plaster, and applies them to give greater strength and coherence to the whole. This is done until the inner surface of the mould is covered of a uniform thickness of an inch and a half to two inches. Thus, bit by bit, the entire mould is put together, and gradually filled in until the last piece has been adjusted and the cast completed. The separate pieces are fixed firmly in situ by application of plaster to the joints; but where there is any strain or extra pressure they are held together by strong iron struts and clamps.

The next and last operation consists in knocking away the mould and laying bare the cast. In order to do this, the moulder and his assistants go to work with mallet and chisel, beginning this time at the top and working downwards. When the iron struts and clamps have been removed, and the plaster holding the parts of the mould in position cut away, the mould itself easily comes off. The workmen are guided in this operation by the yellow colour of the mould. All the plaster of that tint has to be carefully cut away until the cast itself is reached. Portions, however, still remain in the hollows and undercuts, and these have to be deftly worked out with the proper tools. The process resembles nothing so much as digging out a huge fossil from its enclosing matrix, only a fossil is generally embedded in hard stone, while the cast is surrounded with soft plaster. At first the heads of the horses appear, then