What is the name of the device invented by John Napier?
A Napier's Bones 
B Napier's Stones
C Napier's Rows 
D Napier's Beads
Ans A Napier Bones
 What is the name of the device invented by John Napier?
A Napier's Bones 
B Napier's Stones
C Napier's Rows 
D Napier's Beads