The convenience of having only one system of numeration is so well recognised, that there is no need for any discussion. Already the numerical nomenclatures of all nations having any culture have been converted to one, namely, the decimal system, and traces of the ancient use of dozens, scores, fifteens, or sixties, can be found in only a very few of them. Although we count our hours in sixty minutes, we do not date the present as the year thirty-one sixties and seventeen. Yet, in the matters of measure,weight, and value, the old and irksome divisions continue to be used; nay, even in those departments of science which most need laborious calculation, we continue to employ the ancient scale of division.