64 



ing clays into weeks of seven each, and as moreover the 

 solar day is incommensurable with the terrestrial year, and 

 indeed with the period of every planet of the system, deci- 

 mal multiples of the day would be unwarrantably and inju- 

 diciously introduced into the calendar ; but an adherence 

 to the hebdominal period ought not to retard an early 

 reform of the calendar in respect to its monthly division 

 and commencement. Instead of twelve, the solar year 

 consists of thirteen lunar months of twenty-eight days each, 

 with 1J intercalary ; and the vernal equinox is the natural 

 beginning of the year for the northern hemisphere, in 

 which abides the great majority of the human race. 



We have now seen that the use of the metre, the substitute 

 and analogue of the ancient cubit (the human arm), determined 

 from astronomical conditions for the sake of definite accu- 

 racy, strikingly exemplifies in the concrete sense the truth 

 of the adage that " man is the measure of the universe;" 

 but again with equal pertinence is the same truth verified 

 under abstract considerations, for the decimal scale of 

 notation is universally conceded to owe its origin to the 

 number of fingers of the human hand. Among savage 

 peoples, the first attempts at counting are made by present- 

 ing the fingers ; and the simultaneous uplifting of the two 

 hands might have afforded a first glimpse of the idea of 

 classification, in the form of a species containing ten indi- 

 viduals : at least it served to facilitate the consideration 

 of a multitude of things by arranging them into equal par- 

 cels, while ultimately the number ten in each parcel became 

 the radix of quantity. 



Doubts have been expressed whether the denary scale is 

 the most convenient that could have been adopted, and 

 strong claims have been put forth in preference of the duo- 

 denary or scale of twelve. The choice of a scale should be 

 governed in the first place by a desire to combine sim- 

 plicity of operation, with simplicity in the expression of 

 the results of the operations. The lower the radix, the 



