THE METRIC SYSTEM. 195 



that tbis system of multiples and sub-multiples has its most conspicuous 

 illustration in the commonest of all processes — retail payments — and that, 

 too, in the usages of a nation which is above all others mercantile. 



Now it seems to me that the two facts — first, that in early days men di- 

 verged from the decimal division into modes of division which furnished 

 convenient aliquot parts, and, second, that where, as in America, the deci- 

 mal system has been adopted for coinage, they have in the focus of busi- 

 ness fallen into the use of aliquot parts in spite of the tacit governmental 

 dictation— not only prove the need for this mode of division, but imply 

 that, if the metric system were universally established, it would be every- 

 where traversed by other systems. To ignore this need, and to ignore the con- 

 sequences of disregarding it, is surely unwise. Inevitably the result must be 

 a prevention of the desired unity of method ; there will be perpetual incon- 

 veniences from the conflict of two irreconcilable systems. [At the time 

 this prophecy was made, I did not know that in California the " long bits" 

 and "short bits" of the dollar already illustrated this conflict of systems 

 and its evils.] 



I fully recognize the difficulties that stand in the way of making such 

 changes as those indicated — difficulties greater than those implied by the 

 changes which adoption of the metric system involves. The two have in 

 common to overcome the resistance to altering our tables of weights, meas- 

 ures, and values; and they both have the inconvenience that all distances, 

 quantities, and values named in records of the past must be differently ex- 

 pressed. But there would be further obstacles in the way of a 12-notation 

 system. To prevent confusion different names and different symbols would 

 be needed for the digits, and to acquire familiarity with these, and with the 

 resulting multij)lication table, would, of course, be troublesome; perhaps 

 not more troublesome, however, than learning the present system of nu- 

 meration and calculation as carried on in another language. There would 

 also be the serious evil that, throughout all historical statements, the dates 

 would have to be differently expressed; though this inconvenience, so long 

 as it lasted, would be without great difficulty met by inclosing in parenthe- 

 ses in each case the equivalent number in the old notation. 



But, admitting all this, it may still be reasonably held that it would be 

 a great misfortune were there established for all peoples and for all time 

 a very imperfect system when with a little more trouble a perfect system 

 might be established. 



Thus far the letter. And now let me sum up the evidence. 

 Professedly aiming to introduce uniformity of method, the 

 metric system can not be brought into harmony with certain 

 unalterable divisions of space nor with certain natural divisions 

 of time, nor with the artificial divisions of time which all civil- 

 ized men have adopted. As 10 is divisible only by 5 and 2 (of 

 which the resulting fifth is useless), its divisibility is of the 

 smallest ; and having only a makeshift fourth and no exact third, 

 it will not lend itself to that division into aliquot parts so needful 

 for the purposes of daily life. From this indivisibility it has 

 resulted that, though men from the beginning had in their ten 

 fingers the decimal system ready made, they have, in proportion 



