gradually extending to all other commodities. From these
considerations I deduce that the index number of general commodities
may be safely taken as 200 when your book appears. _The reader of your
book has simply to double the figures given by you--that is the
figures of_ 1915 _and_ 1916--_in order to get a rough estimate of
present prices._"

Where exact statements of area and yield are necessary, as in the
study of the intense agriculture of Japan, local measures are
preferable to our equivalents in awkward fractions. Further, the
measures used in this book are easily remembered, and no serious study
of Japanese agriculture on the spot is possible without remembering
them. While, however, Japanese currency, weights and measures have
been uniformly used, equivalents have been supplied at every place in
the book where their omission might be reasonably considered to
interfere with easy reading. The following tables are restricted to
currency, weights and measures mentioned in the book.


MONEY[9]

_Yen_ = roughly (at the time notes for the book were made) a florin or half
a dollar = 100 sen.

_Sen_ = a farthing or half cent = 10 rin.


LONG

_Ri_ = roughly 2-1/2 miles.