210 



THE POPULAR SCIENCE MONTHLY. 



of capital is said to be invested in this adventure, and employment is 

 given to forty or more workmen, all Israelites, with the aid of steam- 

 power. The establisliment already boasts of having cut a fine crystal 

 from South Africa, weighing eighty carats. 



\ / 



Fig. 9. Form of the Rose-Cut. 



Fig. 10. Form of the Table-Cct. 



The process of cutting the diamond is divided by the Jews into 

 several distinct branches, and workmen are educated to perform one 

 part but not another. Thus the cleaving, the cutting, and the polish- 

 ing, have special operators, who become expert in performing well 

 the parts assigned to them, without attempting the others. This 

 course has undoubtedly produced skillful workmen, but w^e see no 

 reason w^liy all the parts may not be perfectly acquired by an intelli- 

 gent mechanic. The art of cleavage, however, requires iact, and 

 ought to include some knowledge of mineralogy. For the particulars 

 of the art of diamond-cutting, we will refer our readers to the inter- 

 esting works of Jeffries, Mawe, and Barbot ; still we briefly mention 

 here some of the forms adopted for the diamond, and how they are 

 produced. 



Fig. 11. The Star of the South. 

 Weight, 1243^ carats. 



Fig. 12. The Great Mogul. Weight, 

 279io carats. 



The table and the rose patterns were the first regular forms adopt- 

 ed by the lapidaries. The first was simply the top of the stone ground 

 flat, with a corresponding flat bottom of less area, with its foui- upper 

 and lower sides parallel to each other. As the light passed througli 

 the stone without much refraction, the beauty of the mineral was not 

 developed by this pattern. It has been stated that the rose-shape was 



