VEGETABLE AND IMITATION 289 



in December, 1913, the prices all referring to 50-kilo lots, 

 equivalent to 110.23 pounds:* 



GRADE OP IVORY NUTS 



Unshelled: 1912 1913 



Guayaquils $4.76-5.24 $3.81-4.76 



Esmeraldas 5.95-6.19 4.64-5.47 



Tumacos 6.19-6.90 4.52-5.00 



Sabinallas 4.28-5.95 3.57-5.24 



Cartagenas 5.24-5.71 3.33-3.81 



Shelled: 



Guayaquils 6.66-6.90 6.19-6.66 



Cartagenas 9.04-9.28 5.00-5.36 



A process of making a substitute for ivory from rubber 

 was invented many years ago, by Frank Marquand, of 

 Rahway, N. J. Two pounds of pure rubber were to be 

 treated with thirty-two pounds of chloroform; as soon as the 

 rubber had dissolved it was to be saturated with ammonia- 

 gas. When it had thus been thoroughly bleached, the 

 solution was to be placed in a vessel, hot water being added, 

 and the material stirred about until the bleaching agents 

 had been entirely removed. The temperature might be 

 raised to 85° C, so as to evaporate the chloroform. The 

 leathery material to which the rubber had been reduced was 

 to be compressed and dried; and then again treated with a 

 little chloroform until it became a thick paste. This was 

 then to be mixed with a powder of zinc phosphate or hy- 

 drate, causing it to become mealy, when it was to be pressed 

 into molds, which were to be heated so as to remove the 

 superfluous chloroform. As soon as the mass was taken 

 from the molds it could be worked in the lathe, and closely 

 resembled ivory. By the addition of certain colouring 



*Consul-General Robert P. Skinner of Berlin, "German Trade in Button-making 

 Materials," Daily Consular and Trade Reports, p. 794; supplementing report published 

 January 6, 1914. 



