MODELLING-COMPOSITIONS, CEMENTS, ETC. 85 



This is a fine, soft, strong wax, and, if vermilion be added, 

 is of a light reddish-brown (owing to the resin). It is very- 

 useful for common work under skins and for other modelling, 

 and was used very successfully for modelling the long stems of 

 the Flowering Rush (see p. 3 S 9), for which purpose it was even 

 better suited than Formula 72, being both softer and tougher. 



75. — M. Peron's " LithocoUe " (Boitard, Naturaliste Prdparateur, p. 251) 

 For fixing-in Glass Stoppers. 



Common resin well pulverised 

 Red ochre in powder 

 Yellow wax 

 Essence of turpentine 



Dissolve the wax and resin, stir well and add the ochre 

 gradually ; when the mixture has boiled for seven or eight 

 minutes, remove from the fire and add the turpentine — the in- 

 structions given, and repeated in every other book, to add this 

 over the fire and to continue boiling, being highly dangerous. 



The proportions may be varied according to the brittleness 

 or elasticity desired in the " lithocoUe." 



76. — Guttapercha Composition (M.B.) 

 Brown guttapercha . . . . i oz. 



Beeswax . . . . . . 2 „ 



Cut the guttapercha small, and heat the ingredients 

 together in a water bath. 



This is a most valuable waterproof composition for making 

 up parts of the mouth or palate, or for setting eyes firmly in their 

 orbits, or for getting a " squeeze," as, although it is hard when 

 cold, it will readily knead up between moderately warm fingers, 

 and reset quite hard. It m,ay also be used, when warm, for 

 smearing stoppers. 



It should be remembered that, for actual india-rubber, 

 C(7«/-naphtha is a solvent. Pure Para rubber should be used. 

 Sometimes turpentine will act as a solvent for this — with heat. 



