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now in the possession of the House of Commons ,and made by Bird , in I76O, be henceforth consideredas the authentic legal standard of length of theBritish empire, so that the distance between thecentres of the two gold pins inserted in that scale,the brass being at the temperature of sixty-two degreesby Fahrenheit’s thermometer, be one yard. And itappears from the experiments made for determiningthe length of the pendulum vibrating seconds atLondon , in a vacuum, and reduced to the level of thesea, that the distance from the axis of suspension tothe centre of oscillation of such a pendulum, is39,1393 inches of the above standard distance: andthat the length of a platina metre at the temperatureof thirty-two degrees o/'Fahrenlieit’s thermometer, sup-posed to be the ten millionth part of the quadrant ofthe meridian, corresponds with 39-3708 inches of thesaid distance.

That superficial measures remain as they are nowdefined by law, namely, that the perch, pole, or rod,be a square of l6f feet, that the acre consist of 160such perches, and so of the rest.

That the standard brass weight of two pounds,also in the possession of the House of Commons , andmade in 1758, be considered as authentic; that one-half thereof, as gravitating in air at the mean height ofthe barometer, and with the thermometer at 62°, behenceforth the legal troy pound of the British em-pire, containing 5760 grains; and that 7000 grainstroy be declared to constitute a pound avoirdupois.

And it appears that a cubic inch of distilled waterweighs in a vacuum, opposed to brass weights in a va-cuum also, at the temperature of 62° of Fahrenheit’s

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