THE REPRODUCTION OF FISHES IN PAPER 257 



the loose fin attached to such part of the base shown upon the 

 body of the fish as was determined upon before. This attach- 

 ment is simply made with paste and tissue-paper, and by pulp- 

 ing a little of the tissue-paper or using wax (Formula 7 1) to fill 

 in crevices, and to make up clearly and naturally. 



When the fin has been cast on both upper and under sur- 

 faces, two moulds will, of course, result, and each mould must 

 be modelled into with tissue or other paper to half the natural 

 thickness of the fin ; then, when pasted together in the manner 

 detailed for the edges of fungi (see p. 375) and the base filled 

 in with composition or wax, it will be of the right thickness. 



Sometimes, owing to various causes^ — nine times out of ten 

 the fault of the operator, — the model will have small blemishes, 

 or will have taken away some specks from the interior of the 

 mould. If this happen, make up with tissue-paper and paste, 

 and brush gently when dry. Oil the model well with colza- 

 oil, and, when absorbed, repeat the dose — perhaps twice — and 

 put away out of the dust. 



The Mounting of the Model 



The finished model was arranged, like that of the shark, 

 with a back -board of wood with keyholes, the wood being 

 3 feet 6 inches in length, by 3 inches, by a ^ inch, feather- 

 edged for a foot from the tail end. At 14 inches from this 

 end a keyhole was made, and another at an interval of 18 

 inches, both being boxed in as described at p. 254. 



The weights of the model were as follow : — 



Model complete, but unmounted . . i lb. 6 oz. 



,, with wood, zinc, packing and backing, under 4 lbs. 



whilst the weight of the actual fish was nearly 30 lbs. 



This system ' of mounting, although, perhaps, not quite so 

 attractive in appearance as when the hollow model is cemented 



17 



