Hamilton Owen Rendel (1843–17 September 1902) designed and installed the original raising mechanism of the Tower Bridge while working for Sir W. G. Armstrong Mitchell & Company of Newcastle upon Tyne.
The mechanism was powered by pressurised water stored in several hydraulic accumulators. Water, at a pressure of 750 psi (5.2 MPa), was pumped into the accumulators by two 360 hp (270 kW) stationary steam engines, each driving a force pump from its piston tail rod. The accumulators each comprise a 20 inches (51 cm) ram on which sits a very heavy weight to maintain the desired pressure.
He was buried at Kensal Green Cemetery in London.
Rendel was a member of a notable family of engineers. His father, James Meadows Rendel, was a civil engineer who married his mother, Catherine Jane Harris. His siblings were:
A cousin, James Murray Dobson, became resident engineer of the Buenos Aires harbour works in the 1880s and 1890s.