( 19 * ) 
that he may draw up a Stone, or a Roll of Sheet* 
Lead, or any other iuch Weight to the Top of an 
Houfe with a Tackle of Five (becaufe this would 
leem feafible from mechanical Principles ) will find 
himfelf miftaken on account of the Fri&ion, which 
will not be furmounted without an additional Force 
of fifty Pounds. 
FINIS. 
A 
ERRATA. 
P AG. 154,1. 24. and p. 356. 1 . penult, read. They may be either of Me- 
tal, or Glafs Plates foiled having their two Surfaces, See. Tranfad. 
Numb. 410. p. 141. 1 . 20. perterritu P. 143. 1 . 15 . Ventriculo, 1 . 18. disjicu 
P. 148. 1 . 3# Jignificari . 1 . 1 1. Ph&nomeno . P, 1 5 1. 1 . ulc. Load, pro Leg • 
LONDON: 
Printed for W. I n n y s and R.Manby, at the 
Weft-End of St. Paul’s Chunh-Tard. 
MDCC XXXIIf. 
