n support of the
foregoing speculations. Those who look sceptically on this attempted
rehabilitation of the earliest epochs of mental development, and who
more especially think that the derivation of so many primary notions
from organic forms is somewhat strained, will perhaps see more
probability in the several hypotheses that have been ventured, on
discovering that all measures of _extension_ and _force_ originated from
the lengths and weights of organic bodies; and all measures of _time_
from the periodic phenomena of either organic or inorganic bodies.

Thus, among linear measures, the cubit of the Hebrews was the _length of
the forearm_ from the elbow to the end of the middle finger; and the
smaller scriptural dimensions are expressed in _hand-breadths_ and
_spans_. The Egyptian cubit, which was similarly derived, was divided
into digits, which were _finger-breadths_; and each finger-breadth was
more definitely expressed as being equal to four _grains of barley_
placed breadthwise. Other ancient measures were the orgyia or _stretch
of the arms_, the _pace_, and the _palm_. So persistent has been the use
of these natural units of length in the East, that even now some of the
Arabs mete out cloth by the forearm. So, too, is it with European
measures. The _foot_ prevails as a dimension throughout Europe, and has
done since the time of the Romans, by whom, also, it was used: its
lengths in different places varying not much more than men's feet vary.
The heights of horses are still expressed in _hands_. The inch is the
length of the terminal joint of _the thumb_; as is clearly shown in
France, where _pouce_ means both thumb and inch. Then we have the inch
divided into three _barley-corns_.

So completely, indeed, have these organic dimensions served as the
substrata of all mensuration, that it is only by means of them that we
can form any estimate of some of the ancient distances. For example, the
length of a degree on the Earth's surface, as determined by the Arabian
astronomers shortly after the death of Haroun-al-Raschid, was fifty-six
of their miles. We know nothing of their mile further than that it was
4000 cubits; and whether these were sacred cubits or common cubits,
would remain doubtful, but that the length of the cubit is given as
twenty-seven inches, and each inch defined as the thickness of six
barley-grains. Thus one of the earliest measurements of a degree comes
down to us in barley-grains. Not only did