524 



SCIENCE 



[N. S. Vol. XXXVIII. No. ! 



stimulated Freneli endeavors for the reform 

 of the carat by bringing it within the scope 

 of the metric system. 



The most eilective worker in this direction 

 was M. C. E. Guillaume, director of the 

 Bureau International des Poids et Mesures at 

 Sevres, who urged the adoption of a carat of 

 200 milligrams before the International Con- 

 gress in April, 1905. In January of the 

 succeeding year, the Chambre Syndicale 

 de la Bijouterie, JoaLIlerie et Orfevrerie of 

 Paris passed a resolution favoring the adop- 

 tion of the metric carat, and in August of the 

 same year the German federation of gem- 

 dealers and jewelers urged its general adop- 

 tion. The movement thus initiated soon 

 spread, and by 1908 Spain had given the new 

 carat a definite legal status, to be followed in 

 1909 by Japan and Switzerland. The adhesion 

 of Italy, Bulgaria, Denmark and Norway fol- 

 lowed in 1910, that of HoUand, Portugal, 

 Roumania and Sweden in 1911. Although it 

 was not until 1912 that it became the legal 

 standard in France and Germany, the law 

 providing for its institution in the former 

 land was passed June 22, 1909. 



As in the case of all efForts to introduce 

 metric weights or measures, the advantages of 

 the new metric carat only very gradually be- 

 came apparent in England and the United 

 States. However, its official adoption by our 

 Treasury Department, on July 1, 1913, as the 

 standard for customs purposes, definitely 

 stamps it with the seal of official acceptation 

 here. 



Belgium has already provided for the use 

 of the new carat and England is expected to 

 fall into line before long, so that by next year 

 it is confidently believed there will be but one 

 standard weight for diamonds, precious stones 

 and pearls, the metric carat of 200 milligrams. 



The paper gives a simple and easy method 

 for converting the old carats of 205 milligrams 

 into the new ones of 200 milligrams, and also 

 offers many interesting details as to the his- 

 tory of the carat and the origin of decimal 

 notation, the first known examples of the latter 

 being found in a translation, published by 



Leonardo of Pisa in 1202, of a work by the 

 ninth-century Arabian mathematician, Al- 

 Khouarazmi. The first use of the decimal 

 point is stated to occur in the arithmetic of 

 Frances Pellos, printed at Turin in 1492. 



There can be little doubt that the adoption 

 of the metric carat in the United States will 

 do much to favor the cause of the metric sys- 

 tem generally in this country, as not only the 

 thousands of jewellers but also the millions of 

 people who buy jewelry will now learn, most 

 of them for the first time, what a kilogram, a 

 gram and a milligram are, when they are told 

 that a carat equals 200 milligrams; five carats, 

 one gram, and 5,000 carats (or 20,000 pearl 

 grains), one kilogram. 



Some additional particulars may be added 

 from advance sheets of M. GuiRaume's report 

 to the International Conference of Weights 

 and Measures. The Argentine Republic, Peru 

 and Servia are all disposed to accept the new 

 carat. In Belgium the law promulgated 

 March 10, 1913, embraces the following ar- 

 ticle : 



In transactions concerning diamonds, pearls and 

 precious stones, the denomination "metric carat" 

 can be given to the weight of 200 milligrams, in 

 derogation of articles 1 and 3 of the law of 

 October 1, 1855. 



The employment of the word " carat " to 

 designate any other weight is prohibited. 



In regard to eventual results M. Guillaume 

 believes that the day will come when the com- 

 merce in precious stones will be confined to 

 the employment of the ordinary metric uni- 

 ties ; the establishment of the carat as a fiftieth 

 part of a grain will then have constituted a 

 stage in this definite reform, and one greatly 

 favoring it. 



George F. Kunz 



SPECIAL ABTICLES 

 THE MECHANISM OF FERTILIZATION 



In previous papers^ I have described the 

 secretion of a substance by the ova of the sea- 



^ Science, N. S., Vol. 36, pp. 527-530, October, 

 1912, and Journ. Exp. Zool., Vol. 14, No. 4, pp. 

 515-574, May, 1913. 



