Driven in under their thumb, as the archetype in 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, 415. Gooch reversing gear, 65. Governors, speed, 67; of motor car, 105. Coal, as fuel, 15; gas, 394; gas plant, we.