Watson-Watt's memorandum "Detection and Location of Aircraft by Radio Methods" was submitted to the Air Ministry in mid-February 1935 (commonly cited as 12 February), before the Daventry demonstration. To prove it, Air Marshal Sir Hugh Dowding provided £10,000 for a demonstration. On the morning of 26 February 1935, a converted Morris van stood in a field near Weedon, Northamptonshire, connected to two dipole antennas and a cathode ray oscilloscope. The BBC's Empire transmitter at Daventry broadcast a continuous 10 kW signal on 49-metre wavelength. An elderly Handley Page Heyford bomber, K6902, flew predetermined passes from 6,000 feet down to 1,000 feet. On the second pass, Wilkins observed a rhythmic beating on the oscilloscope — the reflected echo of the aircraft — detectable at up to eight miles. Watson-Watt turned to A.P. Rowe and said: "Great Britain is an island again."