THE MODELLING OF ROCKS, ETC. 385 



here and there will not matter, for now, be it observed, the 

 imprint is upon the surface, and all erosions or striae upon the 

 original stone are faithfully reproduced upon the paper one. 

 In some cases, where it may not be convenient, owing to the 

 size or shape of the mould, to tie all the pieces together, they 

 may be papered separately and their edges united afterwards 

 to build up the entire stone, the joinings or ridges, when quite 

 dry, being carefully sandpapered. These models must be more 

 carefully dried, otherwise the moulds will split, as stated in 

 previous pages. 



In representing rocks which are supposed to give the exact 

 appearance of the original, one must be careful not to do as 

 was recently done at South Kensington, where, in a large case 

 containing a group of Accipitres at the end of the bird-gallery, 

 a double error was perpetrated, for, with a laudable desire to get 

 as near to nature as possible, pieces of the rocks amongst which 

 these birds nested were brought from Scotland, and moulds 

 were taken from them, but unfortunately the resultant models 

 were made in plaster as thin slabs, whose edges were labori- 

 ously joined together to produce one model, instead of the 

 rocks being cast as just described, and modelled in strong 

 yet light paper in one piece, or, at all events, with fewer and 

 invisible joinings. The most unfortunate thing, however, about 

 these models is, that the rock specimens or patterns brought 

 with such care from Scotland were nearly all newly-fractured 

 pieces, and that, therefore, the models of their sharply angular 

 inside faces are now doing duty for what should be quite a 

 different exposure, viz. a weathered rock -face, and the idea, 

 which was good, is entirely spoiled by want of forethought and 

 technical knowledge. 



Afterwards, both properly-modelled and fancy rocks are to 

 be glued and sanded if the originals have a sandy or rough 

 texture, and in this event the colouring is best managed by 



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