21 



one point to another on the ground is to pace it. Roughly, the 

 foot will be found to be about the third of a step and approxi- 

 mate to twelve inches, which will allow for the rough covering 

 in the form of sandals or shoes, and the step will be very nearly 

 a yard. "With reference to the metre 3937 in., the estimated 

 ten millionth part of a quadrant of a meridian, which corres- 

 ponds very closely with the length of a pendulum beating 

 seconds at the equator, viz., 39013 in., it is only an arbitrary 

 measure after all, and has after each careful measurement of 

 an arc differed, but its approximation to the more primitive 

 yard and three-foot measures suggests the idea that it origi- 

 nated in these ; for the five-millionth or any other fraction on 

 the quadrant might just as well have been adopted, for the 

 matter of that. One reason of: its adoption was that it closely 

 corresponded with the measures in use at the time and pre- 

 viously. It is more than a coincidence. The diagram speaks 

 for itself, and I need not delay over this any longer, but can 

 proceed to a description of the British standard measures. 



The excellence of a principle is in proportion to its sim- 

 plicity ; hence the metric system, which demands only one 

 arbitrary unit, is superior in that respect to ours, which re- 

 quires two., viz., length and weight. In the British system 

 one arbitrary unit of length and one arbitrary unit of weight 

 being agreed upon and fixed by Act of Parliament, all others 

 are derived from these. Hence the yard and pound specially 

 legalised by the Imperial Act of 1878 are called the " Primary 

 Imperial Standards," and all others are called " Derived 

 Standards," capacity beitg based on clause 15 of this Act, 

 which specifies that the gallon shall contain ten pounds weight 

 of distilled water under certain conditions. 



The present standard yard and the pound are the result of 

 natural evolution, their history having been one of progres- 

 sively accurate definition from time to time by Act of Parlia- 

 ment. The French have broken this chain of evolution by the 

 arbitrary selection of the metre as a unit, but, as shown above, 

 even this has been influenced by its prior history. Their idea 

 was to avoid such a thing as an arbitrary standard at all, and 

 if the actual length of an arc could ever be obtained, the thing 

 is accomplished (but this will never be done) ; and in pur- 

 suance of this policy the kilogramme* and litre as units of weight 

 and capacity respectively were based upon the measure of a 

 given weight of water, everything thus being based onh/ upon 

 the metre. In short, we have two arbitrary units, the French 

 have only one. 



*The Kilo = the weight of one cubic decimetre, of water; and the litre con- 

 tains one kilogramme weight of water. 



