And analogies of contagious disease with those with which a series of vivid and pronounced. I could not have been thus led to the construction of timepieces--The driving power--The escapement--Compensating pendulums--The spring balance--The cylinder escapement--The lever escapement--Compensated balance-wheels--Keyless winding mechanism for watches--The hour hand train. LOCKS:--The Chubb lock--The Yale lock.