OF CENTRAL FORCES. 



23 



Fabrenbeii's Scale. 



Standard brass scale, supposed to be 



Hamburgh brass .... 0.0001237 0.0222646 

 English plate brass in form of a 



rod 0.0001262 0.0227136 



English plate brass in form of a 



trough 0.0001263 0.0227386 



Steel rod 0.0000763 0.0137368 



Cast-iron prism .... 0.0000740 00133126 



Glass tube 0.0000517 0.0093138 



Solid glass rod .... 0.0000539 0.0096941 



White glass barometer tube .... 0.0100 



Martial regains of antimony 0.0130 



Blistered steel 0.0138 



Hard steel 0.0147 



Iron 0.0151 



Bismuth 0.0167 



Copper hammered .... . 0.0204 

 Copper eight parts, with tin one 



part 0.0218 



Cast brass 0.0225 



Brass sixteen parts, with tin one 



part 0.0220 



Brass wire 0.0232 



Speculum metal 0.0232 



Spelter solder, viz. brass two part?, 



zinc one . 0.0247 



Fine pewter . . . . . . 0.0274 



Grain tin 0.0298 



Soft solder, viz. lead two parts, tin 



one 0.0301 



Zinc eight parts, with tin one, a little 



hammered 0.0323 



Lead . 0.0344 



Zinc cr speller 0.0353 



Zinc hammered half an inch per 



fobt . . . 0.0373 



