562 



ANCIENT DESEMEKS (HI STEELYARDS. 



instead of tending to restore itself (as an oM-illatini*" l>alanee will), it 

 tends to go farther, so that the side pressed down appears to grow 

 heavier. Such behavior (calh'd "" upsetting" in English) is a grave 

 fault, for. in oixler to weigh, it is necessary not only to shift the 

 fuleruni hack and forth, hut. all the while, to take care that the har 

 is horizontal. 



The Romans perfectly understood this fault. In saying this it is 

 assumed that the halance of Clusiuni does not represent the Hrst in- 

 vented form. It must, surelv. ha\'e had its forei'unn(M-s, which d<)ul>t- 



-Antiiiiinrium, Berlin. Reproduced from Yearbook of German ImperiMl .Xrclioolotficiil 

 Institute, Vf)l. XI U, 1«<J«. One-third natural size. 



less resembled the (Termaii desemers in respect to the position of their 

 point of support, and therefore shai'c^l their inconvenience. In order 

 to use such a l)alance in retail ti'ade it was necessary to have one which 

 would come hack to the position of equilil)rium. It is one thing to 

 weigh a given thing or collection of things, which is almost all that our 



the friction remains just the same whatever the height of the fulcrum; for though the 

 weight acts more nearly at right angles to the radius from the center of rotation to 

 the center of gravity when they are closer together, yet the leverage is smaller in the 

 same proportion. It is, therefore, generally better to rely upf)n optical means, such as 

 a very long tongue, to show small departures from eijuilibrium, rather than to Ijriiigtlic 

 center of gravity so near the axis of rotation tliat the friction can arrest the balance 

 in any sensil)ly oblique position. But tbe most intolerable fault is to bave the center 

 of gravity above the axis of rotation, so that there is a tendency to "upset." — Tr. 



