BUREAU OF STANDARDS 13 



10 milligrams (mg.) = 1 centigram. 

 10 centigrams (eg.) = 1 decigram. 

 10 decigrams (dg.) = 1 gram. 

 1000 grams (g.) = 1 kilogram. 



1 kilogram (kg.) = 2.2046 Ibs. 

 1000 kilograms = 1 metric ton. 



Two advantages which the metric system has over the English sys- 

 tem are: 



(1) It is a decimal system. 



(2) It is already in use in practically all of Europe, and in Latin 

 America. 



Just as we can gather together "one dollar, four dimes, and three 

 cents" into the expression "$1.43," so we can write "two grams, 

 five decigrams, three centigrams, and one milligram" as "2.531 g." 

 A weight consisting of several English units, such as two pounds, six 

 ounces, and fifteen grains, cannot be expressed in pounds without 

 much calculation. 



15. Bureau of Standards. Since it is important that 

 all apparatus used for measuring shall be correct, several 

 governments have established "Bureaus of Standards," 

 to which such apparatus may be sent for the purpose of 

 comparing it with the standard apparatus of the govern- 

 ment. The United States Bureau of Standards (Fig. 13) 

 was established at Washington in 1901. 



Originally the Bureau was only a place for keeping the pound, yard, 

 gallon, bushel, meter, kilogram, etc., up to standard, but it has grown 

 to be much more than this. The many new industries that have 

 arisen in recent years and the application of scientific methods to old 

 industries make new standards necessary. It is also important that 

 both the quantities of the materials that go into manufactured articles, 

 as well as their qualities, or properties (cf. 5), shall be definitely 

 known. Hence the Bureau furnishes standards of measurement for 

 electricity, the unit of light intensity (known as the "candle power"; 



