In 1916 the Medium Tank Mk A was designed by Sir William Tritton.
Each track was powered by a Tyler engine. The driver used a column that would alter the throttle on the engine to determine which direction the tank was to go. When going cross country or for sharp turns the gearboxes were used.
There was 70 gallons of gasoline carried at the front of the tank.
There were three peepholes, with covers and three periscope openings.
Medium B Whippet
The Medium B Whippet was the first tank to have a bulkhead between the engine and the crew.
Medium C Hornet
Tritton also designed the Medium C Hornet in late 1917.