ABOUT MEASURES OF LENGTH. 655 



before completing it, and was succeeded by the Rev. R. Sheepshanks. 

 That gentleman first constructed a bar of brass, which he found to 

 measure 36 '00025 inches, in terms of the lost standard. From this the 

 present "imperial standard yard" known as "bronze 19" was made. 



Before Sir Francis Baily died, he proposed the use of an alloy for 

 standard measures, which is known as Baily's metal. It is composed 

 of sixteen parts of copper, two and a half parts of tin, and one part of 

 zinc. " Bronze 19 " was made of Baily's metal ; it is thirty-eight 

 inches long, one inch wide, and one inch deep. The graduations are 

 upon gold plugs that are sunk into the bar. The lines are sharjD, and 

 are very well adapted to accurate measurement ; they are about -g-oW 

 of an inch in width. This standard was legalized by act of Parlia- 

 ment on July 30, 1855. The original standard " bronze 19," or, as it 

 is also called, " No. 1," is kept in the " Strong Room " of Old Palace 

 Yard. Four copies of it are in existence : one is at the Royal Mint, one 

 is in charge of the Royal Society, one is in the new AVestminster 

 Palace, and the last is at Greenwich Observatory. Forty other copies 

 were made in Baily's metal, and these have been distributed among 

 different Governments, but only two of them are standard at the same 

 temperature as the original. 



From what has been stated, it will be observed that there is no 

 natural unit from which our yard-measure has been derived ; it is 

 merely an assumed unit of length which has been declared a legal 

 standard by the British Parliament. 



The yard-measure of the United States, with which all measures to 

 be verified are now indirectly compared, is known as " bronze bar No. 

 11," which was presented to the Government by the British Board 

 of Trade in the year 1856. It is standard at 61 '79 Fahr. It does 

 not appear, however, that our Congress has ever sanctioned the use of 

 this standard by any enactment. The only standard yard ever legal- 

 ized by that body seems to have been a copy of a part of an old scale 

 by Troughton, which had been used by the Treasury Department pre- 

 viously to 1856. 



There is now a strong movement in favor of the general adoption 

 of the French system of weights and measures in this country. The 

 efforts that have been made to attain this very desirable result have 

 met with great opposition, but this is steadily giving way before ra- 

 tional argument and sound elementary instruction, so that we may 

 safely predict that our very irrational divisions of feet, inches, pounds, 

 and ounces will eventually be abolished, and that a decimal system 

 will take its place. There is a standard metre bar in the possession 

 of our Government, but it has not been declared a standard by Con- 

 gress, although it is used for comparisons. 



The French metre was originally supposed to be equal to the one 

 ten-millionth part of the quadrant of a meridian of the earth passing 

 through Paris. An arc of a meridian which extends from Dunkirk to 



