Footnote 12
Part I, §10.  See the seventh, eighth, and ninth circles in fig. 1.  The names of the months are all Roman.  The month formerly called Quinctilis was first called Julius in B.C. 44; that called Sextilis was named Augustus in B.C. 27.  It is a mistake to say that Julius and Augustus made the alterations spoken of in the text; what Julius Cæsar really did, was to add 2 days to the months of January, August (Sextilis), and December, and 1 day to April, June, September, and November.  February never had more than 28 days till he introduced bissextile years.