Lord Roberts α very nearly terminated all my investigations. My idea both in this and its more successful and famous younger brother, Lord Roberts β, was to utilise the idea of a contractile balloon with a rigid flat base, a balloon shaped rather like an inverted boat that should almost support the apparatus, but not quite. The gas-bag was of the chambered sort used for these long forms, and not with an internal balloonette. The trouble was to make the thing contractile. This I sought to do by fixing a long, fine-meshed silk net over it that was fastened to be rolled up on two longitudinal rods. Practically I contracted my sausage gas-bag by netting it down. The ends were too complex for me to describe here, but I thought them out elaborately and they were very carefully planned. Lord Roberts α was furnished with a single big screw forward, and there was a rudder aft. The engine was the first one to be, so to speak, right in the plane of the gas-bag. I lay immediately under the balloon on a sort of glider framework, far away from either engine or rudder, controlling them by wire-pulls constructed on the principle of the well-known Bowden brake of the cyclist. But Lord Roberts α has been pretty exhaustively figured and described in various aeronautical publications. The unforeseen defect was the badness of the work in the silk netting. It tore aft as soon as I began to contract the balloon, and the last two segments immediately bulged through the hole, exactly as an inner tube will bulge through the ruptured outer cover of a pneumatic tire, and then the sharp edge of the torn net cut the oiled-silk of the distended last segment along a weak seam and burst it with a loud report. Up to that point the whole thing had been going on extremely well. As a navigable balloon and before I contracted it, the Lord Roberts α was an unqualified success. It had run out of the shed admirably at nine or ten miles an hour or more, and although there was a gentle southwester blowing, it had gone up and turned and faced it as well as any craft of the sort I have ever seen. I lay in my customary glider position, horizontal and face downward, and the invisibility of all the machinery gave an extraordinary effect of independent levitation. Only by looking up, as it were, and turning my head back could I see the flat aeroplane bottom of the balloon and the rapid successive passages, swish, swish, swish of the vans of the propeller. I made a wide circle over Lady Grove and Duffield and out towards Effingham and came back quite successfully to the starting-point.