"Some forty years ago, when I commenced to think of the subject, my first idea was to lift my machine by vertical propellers, and I actually commenced drawings and made calculations for a machine on that plan, using an oil motor, or something like a Brayton engine, for motive power. However, I was completely unable to work out any system which would not be too heavy to lift itself directly into the air, and it was only when I commenced to study the aeroplane system that it became apparent to me that it would be possible to make a machine light enough and powerful enough to raise itself without the agency of a balloon. From the first I was convinced that it would be quite out of the question to employ a balloon in any form. At that time the light high-speed petrol motor had no existence. The only power available being steam-engines, I made all my calculations with a view of using steam as the motive power. While I was studying the question of the possibility of making a flying machine that would actually fly, I became convinced that there was but one system to work on, and that was the aeroplane system. I made many calculations, and found that an aeroplane machine driven by a steam-engine ought to lift itself into the air." Sir Hiram then went on to say that it was the work of making an automatic gun which was the direct cause of his experiments with flying machines. To continue the report: "One day I was approached by three gentlemen who were interested in the gun, and they asked me if it would be possible for me to build a flying machine, how long it would take, and how much it would cost. My reply was that it would take five years and would cost L50,000. The first three years would be devoted to developing a light internal-combustion engine, and the remaining two years to making a flying machine. "Later on a considerable sum of money was placed at my disposal, and the experiments commenced, but unfortunately the gun business called for my attention abroad, and during the first two years of the experimental work I was out of England eighteen months. "Although I had thought much of the internal-combustion engine it seemed to me that it would take too long to develop one and that it would be a hopeless task in my absence from England; so I decided that in my first experiments at least I would use a steam-engine. I therefore designed and made a steam-engine and boiler of which Mr. Charles Parsons has since said that, next to the Maxim gun, it developed more energy for its weight than any other heat engine ever made. That was true at the time, but is very wide of the mark now."