832 



SCIENCE. 



[N. S. Vol. XV. No. 386. 



standard and then distributed to the countries 

 interested. The unit of mass or weight, as it 

 is commonly called, is the 'kilogram,' and is 

 defined as the mass of a cubic decimeter of 

 pure water at a standard temperature. The 

 international committee also prepared forty 

 pieces of metal equal in mass to that of the 

 cubic decimeter of water, alike in form and 

 of the same m.aterial as the standard meter, 

 the most permanent metal known. One of 

 these was retained at the International Bu- 

 reau of Weights and Measures as the inter- 

 national kilogram. 



The same precautions were observed in the 

 comparisons with each other and with the 

 one selected as the international standard be- 

 fore distributing them to the respective gov- 

 ernments. Of the two meters and two kilo- 

 grams sent to the United States one of each 

 is preserved as the national standard of length 

 and mass. The others are taken as working 

 standards, and serve as the basis of all com- 

 parisons of length or mass in this country. 

 The fact that the meter is only approximately 

 a natural standard as originally intended has 

 sometimes been used as an objection to the 

 metric system. This, however, is of little 

 importance, since the meter and the kilogram 

 as constructed are as permanent as it is pos- 

 sible to make material standards and are far 

 more accurate than any measurements that 

 can be made of the earth's surface. If at 

 any time a suitable natural standard should 

 be discovered, the meter would simply be de- 

 fined in terms of that standard as it originally 

 was in terms of the earth's quadrant. 



The advantages of the metric system may 

 be briefly stated as its decimal character 

 throughout, the simple relations between the 

 units making it possible to derive all others 

 directly from the unit of length, its elasticity 

 (being equally convenient for the measiire- 

 ment of the smallest or largest objects), the 

 ease with which it is learned and remembered, 

 the saving of time, and the increased accuracy 

 with which computations may be made. These 

 advantages have been proven by a century of 

 use, but that which especially commends it to 

 us at the present time is its international 

 character, since it is the opinion of all who 



are in a position to know that the world must 

 soon come to an international system of 

 weights and measures, and that there is not 

 the slightest possibility of our own system or 

 any modification of it becoming universal. 



THE METRIC SYSTEM AS USED IN SCIENTIFIC WORK. 



Scientific investigators early recognized in 

 the metric system of weights and measures a 

 simple, flexible system equally suitable for the 

 most refined or coarsest measurements, or for 

 purposes of computation. As a result the 

 scientific world to-day enjoys the advantages 

 of a universal system of weights and meas- 

 ures, a fact which has greatly facilitated the 

 development and spread of scientific knowl- 

 edge. The practical applications of scientific 

 work have in many cases been seriously handi- 

 capped or retarded owing to the necessity of 

 converting formulae derived in the metric sys- 

 tem to equivalent formula in the common 

 system. If the formulae and other data used 

 in manufacturing and engineering were uni- 

 versally expressed in the metric system, it 

 would greatly promote the growth and dissemi- 

 nation of such knowledge throughout the en- 

 tire world. 



BENEFITS TO BE DERIVED BY EDUCATIONAL 

 INTERESTS. 



The benefits to be derived from the adoption 

 of the metric system by the educational inter- 

 ests of the country are perhaps the most im- 

 portant that have been brought to the atten- 

 tion of this committee. Estimates made by 

 the Department of Education and others show 

 that the work of at least two thirds of a 

 year in the life of every child would be saved 

 by the adoption of the metric arithmetic. The 

 British Parliamentary committee having in 

 charge a similar investigation estimated the 

 saving of time at one year. This is a matter 

 the importance of which can hardly be over- 

 estimated, taking into consideration the large 

 amount of work to be covered in the cur- 

 riculum of the schools and the enormous sums 

 annually devoted to ediicational work. The 

 metric system is taught in nearly every school 

 in the country. Teachers and pupils alike 

 unanimously testify as to the ease with which 



