THOUGHTS ON COMPARATIVE 

 METROLOGY*. 



IN many respects it resembles comparative philology; one is, 

 the necessity of avoiding general hypotheses. Corresponding 

 to the attempts to deduce all languages from some one assumed 

 to be primitive, or from certain elementary sounds, such as 

 Alexander Murray's nine words, are such hypotheses as that of 

 Gosselin, who, following Bailly, thought that at some early age 

 in the history of the world, the length of the meridian had been 

 accurately determined, and that all the guesses which have come 

 down to us as to the magnitude of the earth were all equally 

 accurate statements of the result of this primitive geodesy, the 

 difference being solved by assuming the existence of a number 

 of different stadia. Touching Bailly's astronomical speculation, 

 it is hard to deny the truth of De Lambre's judgment, who 

 describes it as "le plus cru des songes," or by some equiva- 

 lent phrase. Another general hypothesis seems little better, I 

 mean that of Boeckh, namely, that the weights and measures of 

 antiquity all came from Babylon, and were connected with the 

 use in astronomy of the clepsydra. Thus weight is the primi- 

 tive element, then capacity is derived from weight, and lastly 

 linear measure from capacity ; the unit of the last being the edge 

 of a cube whose volume was the unit of the second ; the unit of 

 the first being the weight of that volume of water. Starting 

 from hypotheses so unproved as these, and modifying them as 

 occasion may require, we may derive anything from anything 

 and explain everything. 



2. In another point of view metrology resembles philology, 

 namely, that similarity is a very bad test of real connection, and 

 that much better evidence is furnished by formal relations than 



* Now first published. 



