OF ARTS AND SCIENCES. 279 



mission International da Metre," for the purpose of settling all doubts 

 in regard to the value and permanence of the unit liases. In 1874, 

 this commission decided to maintain at Paris an "International Bureau 

 of Weights ami .Measures, to be supported by pro rata contributions 

 from all the signing powers, and charged with the care of the proto- 

 t\ pe standards, and with the duty of constructing and verifying copies 

 of those standards, not only for the powers interested, but for other 

 governments, for corporations, and even for private individuals who 

 should apply for them, and who should be willing to pay the expense 

 attending their construction and comparison." 



It is not necessary to record here the considerations which led the 

 Commission to abandon all attempts to establish a standard which 

 should conform to the natural unit, in accordance with which the ori- 

 ginal meters were constructed. It is sufficient to say that the Com- 

 mission decided that the " Metre des Archives" shall be recognized and 

 perpetuated forever as the true base of the measure of extension, with- 

 out regard to the doubtful questions which have been raised concern- 

 ing its correspondence with its theoretical value. The first resolution 

 of the " Convention du Metre," signed May 20, 1875, reads as fol- 

 lows : " For the execution of the international meter, the Metre des 

 Archives, in the state in which it is found, is taken as the point of 

 departure." 



The Convention adopted twenty-one resolutions respecting the meter, 

 of which the most important are the following : — 



" IV. Though deciding that the new international meter shall be a 

 line-meter, of which every country shall receive identical copies, con- 

 structed at the same time as the line prototype, the Commission will 

 nevertheless undertake to construct a certain number of end-measure 

 standards for the countries which shall express a desire for them, 

 and the equations of these end-meters with respect to the new line 

 prototype shall be determined with equal care by the International 

 Commission. 



" V. The international meter shall be of the length of the meter 

 at 0° C. 



- VI. In the fabrication of the meters, an alloy shall be employed, 

 composed of 90 parts of platinum and 10 parts of iridium, with an 

 allowance of two per cent variation, more or less." 



'•IX. The bars of platinum-iridium, upon which the lines are to be 

 traced, shall be 102 centimeters in length, and their transverse secbion 

 shall be represented by a model described in a note by M. Tresca." 



" XIII. The method of M. Fizeau shall be employed in determin- 



