The Dime = .1 a little more than 2. kentals. Cent = .01 a little more than 20 lb. Mill = .001 a little more than 2 lb. Decimmil = .0001 about 3½ oz. avoirdupois. Centimmil = .00001 a little more than 6 dwt. Millionth = .000001 about 15 grains. Decimmillionth = .0000001 about 1½ grains. Centimmillionth = .00000001 about .14 of a grain. Billionth = .000000001 about .014 of a grain. With respect to our coins, the pure silver in a dollar being fixed by law at 347¼ grains, and all debts and contracts being bottomed on that value, we can only state the pure silver in the dollar, which would be very nearly 23 millionths. I have used loose and round numbers (the exact unit being yet undetermined) merely to give a general idea of the measures and weights proposed, when compared with those we now use. And in the names of the subdivisions I have followed the metrology of the ordinance of Congress of 1786, which for their series below unit 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° 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,