xx AGRICULTURAL WEIGHTS AND MEASURES. 



LONG MEASURE. 



CORN MEASURE. 



FRENCH WEIGHTS AND MEASURES. 



What is called a standard in weights and measures is merely an authority ; and this in rude ages 

 is founded on custom, or some arbitrary quantity ; while, in the progress of improvement, a stand tid is 

 derived from nature. Among the various natural standards, the two following may be considered the 

 best : — 



1. The length of a pendulum that vibrates seconds of mean solar time. 



2. The length of an arc or portion of a meridional circle. 



From the measurement of a meridional arc in France ; the length of the quadrantal arc was computed ; 

 and the ten-millionth part of this quadrant is the metre, which is the standard unit for all French mea- 

 sures. 



The standard unit for all weights is the gramme, which is the weight of a cubic vessel of water ol the 

 greatest condensation and purity ; the side of such cube being the hundredth part of the metre. 



From these two units the other measures are denied by decimal division or multiplication, and hence 

 ths system is generally called 



