CASEIN PAINTS. 51 



hand, these colours are very suitable for stone surfaces and 

 especially for freshly prepared cement walls. The surface to 

 be painted and the painting material being of the same chemical 

 nature, the result of the cohesion is very good. 



Casein-lime colours cannot be recommended for painting over 

 surfaces already covered with old lime or oil paint. Thorough 

 examination of the surface to be painted should be made before 

 casein-lime colours are applied. The colour should first be 

 mixed with a little water, about half of the weight of the dry 

 colour ; the pulp thus obtained should be allowed to stand for 

 a quarter or half an hour, and then about twenty or twenty-five 

 parts more of water should be added and stirred in. The 

 painting material is then ready for use. If a glossy coat is 

 desired, only about ten parts of water are used in the second 

 application ; the ready-made pulp is then thick and more like 

 an oil colour in appearance. If well made from suitable 

 materials and carefully applied, casein-lime colours give ex- 

 cellent results and are found to be thoroughly satisfactory. 

 The success of the casein-lime colour depends on the suitable 

 application, and rests upon a thorough knowledge of the 

 character of the paint in question and its relations with the 

 surface to be painted. 



KISTORY'S RECIPE FOR CASEIN PAINT AND VARNISH. 



Professor Modets Kistory, of Moscow, recommends for 

 casein varnish a mixture of 32 parts of sifted curd and 32 

 of water, stirred together at 64 F., the pap being forced 

 through a metal sieve in order to secure more intimate ad- 

 mixture and subdivision of the particles. Meanwhile, some 

 freshly burned lime is gradually slaked with water at the 

 above-named temperature, so as to crumble down to a fine 

 powder. Of this powder | part is mixed with 3 parts of 

 water, triturated and then filtered through blotting-paper. 

 The two ingredients are finally mixed together by stirring, 



