550 TRANSACTIONS OF THE 



forgotten Talleyrand, Bisliop of Autun, in 1790. He recom- 

 mended to the academy the length of the second's pendulum as 

 a standard, but the academy preferred the metre, and the national 

 assembly adopted it. England has been most pleased with 

 Talleyrand's plan These natural standards look exceedingly 

 well on paper, highly pliilosophical, work nicely in scientific cal- 

 culations. But there are other folks in the world besides the 

 philosophers, and other calculations besides dynamical and geo- 

 detical. A national system of weights and measures ought to suit 

 the greatest number of people. 



The pendulum standard of England is in length 39 inches and 

 tW-to- '^^^^ French standard, the metre is 39 inches and 

 tVoVoV i^ length. These cannot serve for a mechanic's rule, 

 nor is there any thing so important as the foot rule. The sun 

 never sets on this rule ! By means of its slide it is a perfect 

 gauge for measuring the depth of holes and the internal diame- 

 ters of cylinders within its range. It is a ready and good calcu- 

 lating machine, easily learned — placed by the side of a metre it 

 is as superior to it in utility as a locomotive is to a wheelbarrow. 

 What would Fairbairn, Maudslay, Penn or Whitworth say if they 

 saw one of their mechanics take a French metre out of his pocket, 

 unfold it, place it on the nearest clear surface to straighten its 

 ten decimetres, then call upon another hand to help use it and 

 then proceed to fold up the nine jointed snake-like monster and 

 put it into any of his pockets ? Would they call it a time saving 

 instrument ? They would prefer the old rule with all its faults, 

 and they are not little ones; but give it four-eighths of an inch 

 more length so as to make it contain one hundred instead of 

 ninety-six eighths, thus making it decimal, and you have a rule 

 nearly perfect, fit to be the fundamental unit of a system of mea- 

 sures and of weights. The advocates for a natural standard say 

 tiiat if lost it is readily recovered. 



Cassini and La Hire brought before the French academy the 

 question of ancient measures. Cassini tried to find out the Roman 

 road measures, from the distances given by Roman writers of 

 certain well known places, but the roads had undergone change, 

 and it was uncertain from what point they were measured. 



La Hire tried to find the measure of a Roman foot from two on 

 the sepulchres of two architects and from the measures of certain 

 Roman ruins; but these things had decayed. If you could 

 compel all the mechanics in France to use the metre for one 

 w^eek you would have more valuable time lost than all the 

 savans would save in a century ! 



