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the distance, or as the proportions in chemical
combinationssuch as, for instance, of the
primitive ingredients which, together, make
up common salt. Weights and measures are
therefore, bye-laws of nature; and it is of
the utmost importance to fix upon a unit
whose invariable representative is to be found
in the material world in which we dwell.
What have we done in that respect ? We
have a measure, the assumed length of the
human foot; and another, the inch, the
imagined breadth of the human thumb; as if
all men were cast, like rifle-bullets or leaden
idols, in the same iron mould, and had feet
and thumbs of uniform dimensions. The old
French foot and inch are longer than the
English ones; but if ethnical differences had
been taken as a guide, they ought, I think, to
have been somewhat shorter. We have a
liquid gallon, which might perhaps have
passed as a factor of the contents of the
human stomach during the age when ale-
and-beer-drinkers measured their powers by
the number of gallons they were able to
swallow, but which, happily, is either obsolete
or voted low now, as such. And our dry
measures! We have dry measures with no
better natural standard than existed in the
times when a cat suspended by the tail with
her nose touching the ground, had to be
covered by a heap of wheat.

The French reformers made their lineal
measure, or long measure, as we call it, the
foundation of all the rest; and, as the
terrestrial globe on which we dwell shows no
symptoms either of increasing in obesity, or
of wasting away in a galloping consumption,
they took their measurements from the earth
herself. They ascertained how many yards
it would require to put an exact-fitting girdle
round, not her waist or abdomen, for that
would vary from the equator upwardsbut
from head to foot, passing through the poles
both north and south. Such a girdle as this,
from top to toe, is invariable, to whichever
part of the earth we apply it; and it is
called a meridian, from the Latin meridies,
because every such girdle strapped round the
world is fully exposed to the noon-tide sun
once in every twenty-four hours. An infinite
number of meridians may thus be supposed
to be twisted round the globe, exactly as the
threads lie closely side by side on a ball of
twine. Every inch of ground, as we proceed
from east to west, has its own meridian of
precisely equal length to that of its next door
neighbour. If you trace anywhere a sun-dial
on the ground, the line where the shadow
of the upright gnomon falls exactly at the
moment of noon, corresponds to the meridian
line of that special spot, and might be
continued, of course, perfectly straight both north
and south till it reached the poles.

For convenience, the quarter only of the
entire meridian was taken; namely, from the
north pole to the equator, for the reason that
it subtends a right angle exactly, which, as a
fixed and invariable term, must be the unit
of angular measure. But when the exact
length of the quadrant of the terrestrial
meridian was known, although it possessed
the great advantage of being a natural and
invariable standard, it also proved of rather
inconvenient length for the measurement of
tapes, ribbons, and even roads. It was, therefore,
judged proper to cut it up into a stated
number of equal bits, and to take one of
those bits as the unit to start from. A mode
of division was fixed upon which should give
portions successively ten times less than the
parts divided. Accordingly, the quadrant
was first divided into ten equal portions, and
then each portion into ten others, and so on;
or, what comes to the same thing, the
quadrant of the meridian was successively
divided into tenths, hundredths, thousandths,
and so on. The first sub-divisions being
evidently too long to furnish a measure
convenient for practical purposes, and quite
incapable of serving as the unit of ordinary
measurement, the division by ten was
continued till the quadrant was divided into ten
million parts, and it was found that each ten-
millionth part, which was about three feet
and an inch of the old French measure,
fulfilled the conditions requisite for every-day
usefulness. This length was adopted as the
unit of measurement, from which all others
were to be deduced; and it was called a
METRE, a word which means neither more nor
less than a measure. Thus, mètres fulfil in
French measurement, the office performed by
English yards, than which they are more than
a trifle longer.

The value of the mètre, and of its subdivisions
and multiples, arises from the circumstance
that such measures have a real basis,
always existing and invariable; since the
definite length, from which they derive their
origin, is taken from a natural standard.
The only human agency applied is, the way
in which this stated length is divided, and
the choice of certain special divisions, which,
appeared the most suitable for national
convenience. This standard length may
therefore be compared to the lengths of
the day, or of the year, both which are
natural lengths, measured by the revolution
of the earth on its axis, or round the
sun. All that remained for men to do,
was to divide the length of the year into
twelve months, that of the day into twenty-
four hours, and that of the hour into sixty
minutes; but they were equally at liberty, as
has been attempted, to establish a decimal
division of time. Although measurement by
mètres is a French invention, it has the same
claim to be adopted by the whole family of
the human race. If all the mètre-measures
in the world (whether made of wood, ribbon,
ivory, or metal) were utterly destroyed and
made to disappear, the mètre itself could still
be found again, to half a hair's breadth, by
repeating the same calculations and processes