weight consists of 112 pounds, the half hundred of 56, and the quarter hundred of 28, the eighth of a hundred of 14, and the sixteenth of a hundred of 7 pounds; that the troy pound consists of 5,760 grains, 7,000 of which grains are of equal weight with the avoirdupois pound that the bushel is a vessel of capacity of 2,150.42 cubic inches, the wine gallon a measure of 231, and the ale gallon a measure of 282 cubic inches.

The various modes of division of these measures and weights, the ell measure, and the application of the foot to itinerary, superficial, and solid measure, producing the perch, rood, furlong, mile, acre, and cord of wood, may be left to the established usage, or specifically declared, as may be judged most expedient. The essential parts of the whole system are, the foot measure, spring water, the avoirdupois pound, and the troy grain.

2. For the purpose of uniformity, it would be desirable to obtain a copy, as exact as the most accomplished art could make it, of the standard yard of 1601, in the exchequer of Great Britain, made of the same material, brass, but divided with all practicable accuracy into three feet, and thirty-six inches, and each inch further divided into tenth and hundredth parts. This rod, with the words, "stand"ard yard measure of the United States-three feet-thirty-six "inches:" and the date of the year engraved on one of its sides, should be enclosed in a wooden case, and deposited for safe-keeping in one of the offices at the Capitol. From the foot measure of this yard, the standard bushel, and two gallons, should be made. The avoirdupois pound, and the troy weight of 256 ounces, should be made exactly conformable to the standards in the exchequer. The weights of 56, 28, 14, and 7 pounds avoirdupois, should be made exact multiples of the pound weight. But no subdivisions of the bushel or gallons, or of the avoirdupois pound, should be placed among the standards. An enactment, that no subdivisions of the standards, other than in the due proportion to them, should be legal, would avoid the inconvenience and the varieties which multiplied material standards always produce. All the standards should, like the yard, have their names, as standards of the United States, the date of the year, and a designation of quantity engraved upon them. On the bushel, for instance," 2150 cubic inches;" on the wine and ale gallons, respectively, 231 and 282 inches; on the avoirdupois pound "7,000 grains troy weight, avoirdupois pound," on the troy weights "256 "ounces-12 ounces, and 5,760 grains to the pound troy weights." These standards, all enclosed in suitable cases, to preserve them from injury, and, as effectually as possible, from decay, should be deposited in the custody of a sworn and responsible officer, with the standard yard.

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3. These national standards being thus made and deposited, exact copies of them should be made of the same materials, substituting for the words "standard of the United States," engraved upon the originals, the words "United States" standard, state "of-" and these copies should be transmitted to the executives of every state in

the Union. The standard for the territories might leave the name of the state to be engraved when the territory should pass to that condition and the standards for the District of Columbia might properly be committed to the charge of the clerk of the supreme court of the United States.

4. It should be made the duty of the collectors, surveyors, and naval officers of the customs, the registers of the land offices, and receivers of public moneys, of the postmaster general, and all postmasters, the quartermasters, and commanding officers at military posts of the army, the commanding officer and purser of every vessel of the navy, the commanding officer at the military academy, of all Indian agents, and of the marshals of the several judicial districts of the United States, to ascertain, and to certify in writing, upon oath, to the heads of their respective departments, that the weights and measures used by them, in the discharge of their official duties, are conformable to the standards of the United States. And to secure the future observance of this uniformity, every such officer, civil or military, to be appointed hereafter, should, together with the oath to support the constitution of the United States, have administered to him an oath that he will, in the discharge of his official duties requiring the employment of weights and measures, scales and beams, use such as are conformable to the legal standards of the United States, and not knowingly any others. To the penalties of removal from, and disqualification for office, might be added a right of action for damages, given to any person injured by the wilful neglect or refusal of any such officer to observe the requisitions of the law.

5. The offence of fraudulently or wilfully making or selling any weight, measure, scales, or beam, to be used as conformable to the United States' standards, and not conformable, might be made punishable by fine and imprisonment, upon presentment and conviction before the circuit courts of the United States.

The existing laws of all the states should be declared, so far as they are conformable to the act of Congress fixing the standard, to remain unrepealed and in full force. All sealers of weights and measures, and all persons appointed under the authority of the several states for the custody of standards, should be required to ascertain them to be conformable to the standards of the United States. It is scarcely possible that any law of the United States to establish uniformity of weights and measures throughout the Union, should be made effectual, without the cordial aid and co-operation of the state legislative and executive authorities. This is one of the most powerful reasons which have led to the conclusion, that, in fixing the standard, all present innovation should be avoided. The standards of all the states are now, or by their laws should be, the same as those herein proposed, excepting only the Connecticut bushel, the change in which will be inconsiderable. Several of the states have systems well organized, and in full operation for the uniformity of their weights and measures. The standards of many of them are incorrect; some from careless usage and decay; others from having been copies

of copies made without much attention to accuracy; and, others from having transferred to this country all the varieties of the original standards in the exchequer. The object of the act, the substance of which is now proposed to Congress, would be, to make the uniformity already existing by the laws and usages of every part of the Union more effectual and perfect in point of fact. The table of a return from the several custom houses of the United States will shew the extent of the existing varieties; and while they add new demonstration of the justness of the sentiment universally prevailing, that the authority delegated to Congress by the constitution, of fixing the standard, should be exercised without delay, they also show that the best exercise of that authority will be by making it essentially auxiliary to the efficacy of the existing state laws.

In the consultation which it is proposed that the President of the United States should be requested to authorize and conduct with foreign governments, with a view to future, more extensive, and perfect uniformity, there is one object, which, it is presumed, may be accomplished with little difficulty or expense, and by means of which the standard from nature of the new French system, the metre, may be engrafted upon our system without discomposing any of its existing proportions.

In all the proceedings, whether of learned and philosophical institutions, or of legislative bodies, relating to weights and measures within the last century, an immutable and invariable standard from nature of linear measure has been considered as the great desideratum for the basis of any system of metrology. It is one of the greatest merits of the French system to have furnished such a standard for the benefit of all mankind, in the metre, the ten millionth part of the quarter of the meridian. Of the labors, and researches, and liberal expense, and art, and genius, which have been lavished by France upon this operation, and of the success with which it has been accomplished, the notice which it amply merited has already been taken in this report. Since this great and admirable undertaking has been achieved, a disposition to detract from its merit and usefulness has been occasionally manifested. Some philosophical speculators have started doubts whether the metre is really the forty millionth part of the circumference of the earth; and indeed whether such a measure can, with perfect accuracy, be ascertained by human art. Other standards from nature have been suggested as preferable to the arc of the meridian: individual passions and antisocial prejudices have insinuated themselves into the inquiry: and the question between the metre and the pendulum has almost festered into a test of party controversy, and an engine of national jealousy. In the establishment of the French system, the pendulum, as well as the meridian, has been measured; but the standard was, after long deliberation, after a cool and impartial estimate of the comparative advantages and inconveniences of both, definitively assigned to the arc of the meridian, in departure

* See Appendix.

from an original prepossession in favor of the pendulum. Two reasons are deemed decisive for concurring in the principle of this determination; one, that the earth being the greatest object of actual measurement within the physical powers of man, an aliquot part of its circumference is the only measure, which, applicable to that object, is also equally applicable to every other purpose of weight or mensuration; and the other, that this standard once settled is invariable, while the pendulum, being of different lengths in different latitudes, is essentially defective in one of the most important principles of uniformity, that of place or capacity of application to every part of the earth.

It is proposed, therefore, to discard all consideration of the pendulum as the theory of its vibrations, however interesting in itself, is believed to be, since the definitive determination of the metre, useless, with reference to any system of weights and measures. Nor is it of more importance to know whether the metre really be, within the ten thousandth part of an inch, an exact aliquot part of the circumference of the earth. An error to that, or even to a greater extent, admitted to be possible, leaves for all practical purposes of human life, even including the operations of geography and astronomy, the metre as perfect a standard for weights and measures as any other that ever was devised, and a much more perfect one than the pendulum.

It is therefore submitted to the consideration of Congress, that, in the act for fixing the standard of weights and measures for the United States, together with a definition of the foot, its exact proportion to the standard metre of France should be declared: to effect which purpose with the utmost attainable accuracy, it would be necessary to compare together the identical measure, to be used hereafter as the standard linear measure of the Union, with the standard metre in platina, deposited in the national archives of France. It is not doubted that the French government would readily give their assent to this operation, and would agree that it should be performed in such manner as to settle, definitively, for the future use of both countries, the exact proportion to the ten thousandth part of an inch, between the foot measure of the United States and the metre. From the perfection which the instruments used for comparing together measures of length have attained, accuracy to that extent may be effected. But the necessity of such an operation for the definitive settlement of this proposition is apparent, from the fact, that the comparisons hitherto made in France, and in England, and in the United States, though all made with all possible care, have terminated in results so different, that it would scarcely be safe to assume either of them as the proportion to be declared by a legislative act.

In the attempt to determine distances of space less than the 200th part of an inch, the experiment is met by obstacles, in the temperature and pressure of the atmosphere, and in the different degrees of their influence upon the matter to be measured. Heat and cold, moist and dry, high and low, affect the metals of which measures are composed with various degrees of dilatation and contraction. Brass, the metal

of which the English standards are formed, being a compound metal, is variously dilatable: and, although tables have been formed of the degrees in which the simple metals are expanded by heat, according to the scale of the thermometer, yet, as those tables, made by different men, do not agree, no perfect reliance can be had upon them. As yet no experiments of admeasurement, made by different persons, at different times, but of the same standards, have exhibited results, approximating within one two-hundredth part of an inch of a contrary result, the examples are numerous, and so remarkable that they deserve to be noticed more particularly.

In the year 1797, sir George Shuckburg Evelyn measured, with Troughton's microscopic beam compass and scale, all the standards. at the exchequer; the scale made by Sisson for Graham in 1742, the parliamentary standards of 1758 by Bird, the scale used by general Roy for the measurement of the base, and several others. The result of his experiment was published in the transactions of the Royal Society of that year. He found that the standard yard of Elizabeth at the exchequer marked 36.015 inches, Bird's parliamentary standard of 1758, 36.00023, and general Roy's scale 36.00036, on the scale of Troughton.

In the year 1818, captain Henry Kater, one of the commissioners of the prince regent, with the same microscope beam compass of Troughton, measured the same scale of general Roy, and found 39.4 inches on the latter to be equal to 39.40144 on the scale of Troughton. The difference between these two results is 105 or rather more than a hundredth part of an inch. Captain Kater, to account for it, supposes, that when sir George Shuckburg made the comparison, the two scales were not at the same temperature: but sir George Shuckburg, in his own account of his experiments, expressly mentions his leaving together another of the scales with that of Troughton, by which he measured it 24 hours, that they might acquire the same temperature; and marks the state of the thermometer (51.7) when he measured the scale of general Roy. Captain Kater states the thermometer, when he measured it, to have been at 70.

A difference equally striking has happened in the experiments made in France and England, to ascertain the relative proportions of the English foot and of the French metre. The result of numerous experiments, made in France under the direction of the National Institute, or Academy of Sciences, has been to announce the metre to be precisely equal to $9.3824 English inches. The result of captain Kater's experiments, after numerous others under the direction of the Royal Society, is the declaration, that the French metre is equal to 69.3708 English inches. The difference is of an inch, more than one hundredth part, and as near as possible the same as that of the experiments of captain Kater and of sir George Shuckburg EveJyn, upon the scales of Troughton and of general Roy.

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A very interesting account of experiments made in this country by Mr. Hassler, to ascertain the length of the metre, is subjoined to this report, from which the mean length of four standard metres was