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adopted the Roman numerals。 For that above unit the Grecian is
convenient； and has been adopted in the new French system。
We come now to our last question； in what form shall we offer
this metrical system to the world？ In some one which shall be
altogether unassuming； which shall not have the appearance of taking
the lead among our sister institutions in making a general
proposition。 So jealous is the spirit of equality in the republic of
letters； that the smallest excitement of that would mar our views；
however salutary for all。 We are in habits of correspondence with
some of these institutions； and identity of character and of object；
authorize our entering into correspondence with all。 Let us then
mature our system as far as can be done at present； by ascertaining
the length of the second pendulum of 45 degrees by forming two
tables； one of which shall give the equivalent of every different
denomination of measures； weights and coins in these States； in the
unit of that pendulum； its decimals and multiples； and the other
stating the equivalent of all the decimal parts and multiples of that
pendulum； in the several denominations of measures； weights and coins
of our existing system。 This done； we might communicate to one or
more of these institutions in every civilized country a copy of those
tables； stating as our motive； the difficulty we had experienced； and
often the impossibility of ascertaining the value of the measures；
weights and coins of other countries； expressed in any standard which
we possess； that desirous of being relieved from this； and of
obtaining information which could be relied on for the purposes of
science； as well as of business； we had concluded to ask it from the
learned societies of other nations； who are especially qualified to
give it with the requisite accuracy； that in making this request we
had thought it our duty first to do ourselves； and to offer to
others； what we meant to ask from them； by stating the value of our
own measures； weights and coins； in some unit of measure already
possessed； or easily obtainable； by all nations； that the pendulum
vibrating seconds of mean time； presents itself as such an unit； its
length being determined by the laws of nature； and easily
ascertainable at all times and places； that we have thought that of
45 degrees would be the most unexceptionable； as being a mean of all
other parallels； and open to actual trial in both hemispheres。 In
this； therefore； as an unit； and in its parts and multiples in the
decimal ratio； we have expressed； in the tables communicated； the
value of all the measures； weights and coins used in the United
States； and we ask in return from their body a table of the weights；
measures and coins in use within their country； expressed in the
parts and multiples of the same unit。 Having requested the same
favor from the learned societies of other nations； our object is；
with their assistance； to place within the reach of our fellow
citizens at large a perfect knowledge of the measures； weights and
coins of the countries with which they have commercial or friendly
intercourse； and should the societies of other countries interchange
their respective tables； the learned will be in possession of an
uniform language in measures； weights and coins； which may with time
become useful to other descriptions of their citizens； and even to
their governments。 This； however； will rest with their pleasure； not
presuming； in the present proposition； to extend our views beyond the
limits of our own nation。 I offer this sketch merely as the outline
of the kind of communication which I should hope would excite no
jealousy or repugnance。
Peculiar circumstances； however； would require letters of a
more special character to the Institute of France； and the Royal
Society of England。 The magnificent work which France has executed
in the admeasurement of so large a portion of the meridian； has a
claim to great respect in our reference to it。 We should only ask a
communication of their metrical system； expressed in equivalent
values of the second pendulum of 45 degrees as ascertained by Messrs。
Borda； Coulomb and Cassini； adding； perhaps； the request of an actual
rod of the length of that pendulum。
With England； our explanations will be much more delicate。
They are the older country； the mother country； more advanced in the
arts and sciences； possessing more wealth and leisure for their
improvement； and animated by a pride more than laudable （*）。 It is
their measures； too； which we undertake to ascertain and communicate
to themselves。 The subject should therefore be opened to them with
infinite tenderness and respect； and in some way which might give
them due place in its agency。 The parallel of 45 degrees being
within our latitude and not within theirs； the actual experiments
under that would be of course assignable to us。 But as a corrective；
I would propose that they should ascertain the length of the pendulum
vibrating seconds in the city of London； or at the observatory of
Greenwich； while we should do the same in an equi…distant parallel to
the south of 45 degrees； suppose in 38 degrees 29'。We might ask of
them； too； as they are in possession of thestandards of Guildhall； of
which we can have but an unauthentic account； to make the actual
application of those standards to the pendulum when ascertained。 The
operation we should undertake under the 45th parallel； （about
Passama…quoddy；） would give us a happy occasion； too； of engaging our
sister society of Boston in our views； by referring to them the
execution of that part of the work。 For that of 38 degrees 29' we
should be at a loss。 It crosses the tide waters of the Potomac；
about Dumfries； and I do not know what our resources there would be
unless we borrow them from Washington； where there are competent
persons。
（*） We are all occupied in industrious pursuits。 They abound
with persons living on the industry of their fathers； or on the
earnings of their fellow citizens； given away by their rulers in
sinecures and pensions。 Some of these； desirous of laudable
distinction； devote their time and means to the pursuits of science；
and become profitable members of society by an industry of a higher
order。
Although I have not mentioned Philadelphia in these operations；
I by no means propose to relinquish the benefit of observations to be
made there。 Her science and perfection in the arts would be a
valuable corrective to the less perfect state of them in the other
places of observation。 Indeed； it is to be wished that Philadelphia
could be made the point of observation south of 45 degrees； and that
the Royal Society would undertake the counterpoint on the north；
which would be somewhere between the Lizard and Falmouth。 The actual
pendulums from both of our points of observation； and not merely the
m