t'OL. Ll] PHILOSOPHICAL TftANSACTIONS. 487 



of any one of them with each other, which is the only way to discover the mea- 

 sure by which a building was constructed. 



With this view therefore Mr. R. carefully examined the measures of the build- 

 ings contained in that treasury of ancient Roman architecture, entitled Les Edi- 

 fices antiques de Rome, and published at Paris by Mons. Desgodetz in the year 

 l682. In order to this, it was first necessary to ascertain the proportion of the 

 Paris foot (the measure used by this author) to some known English standard. 

 The Paris foot is one 6th part of the toise in the Chatelet ; which was renewed 

 in the year 1668, and the new standard has continued in use ever since. 



In the year 1742 the r. a. s. at Paris, at the request of the r.s. of London, 

 sent over a measure of half the toise of the Chatelet; from which Mr. Graham 

 determined the proportion of the Paris foot to that of London, to be as 1 005.4 1-f- 

 to 1000. Mons. le Monnier, of the r. a. s., from the same originals, found 

 their proportion as 864 to 811, or as 1065.351 to 1000. The difference 

 is inconsiderable, and we may, without injustice to Mr. Graham's known skill 

 and accuracy in these matters, suppose their true proportion to be as 1065.4 to 

 1000. Mr. Graham's measure of the London yard, together with that of half the 

 toise of the Chatelet, are deposited in the archives of the r. s. at London; and of 

 the k.a.s. at Paris; and wheneverMr. R. mentions the London foot, without speci- 

 fying any particular standard of it, he would be understood to mean this measure. 



In this inquiry we are to seek a common measure to the several parts of each 

 building, that shall not diflfer very widely from some assumed magnitude of the 

 Roman foot : and though we might take this assumption from any of the ancient 

 foot-rules now remaining, yet the nearer it is taken to the truth, the better guide 

 it will be to us, and the more it will facilitate our inquiry. Now as a mean 

 measure derived from these rules will probably be nearer the truth than either 

 the greatest or the least of them, so one that shall include such other remains o^ 

 antiquity, as have hitherto been made use of to discover the measure of the Roman 

 foot, will be still more unexceptionable, as the writers on this subject are not 

 agreed, which of the different authorities is to be preferred. The representations 

 of this foot in sculpture are 4 in number; one on the sepulchral monument of 

 Cossutius, formerly in the Colotian gardens at Rome; another on that of Sta- 

 tilius, in the Belvedere; a 3d on that of M. Ebutius in the Villa Mattel; and 

 the 4th on a marble, without incription, dug up of late years in the Via Aurelia, 

 which being in the possession of the Marquis Capponi, is called by P. Revillas 

 the Capponian foot. Most of the early writers on this subject have expressed 

 their measure of the Roman foot by a diagram ; and Snellius observing that the 

 paper contracted in drying, after the impression was taken off, endeavoured to 

 make a proper allowance for it. But Greaves, finding the measures of these 

 figures to differ in different copies of the same impression, took another method ; 



