Many runs along the track were made to test the working of this great apparatus before trusting it to launch forth in free flight. Dynamometers gave independently the thrust of the screws, and the lift of the wings on the front and rear axles. The ascensional planes for controlling the fore and aft equilibrium were tested during the run, as also the practical operation of the propelling plant. During the trials of 1893 the machine frequently lifted clear of the lower track, and flew forward resting against the guard rails above the wheels. Finally, on a gusty day, the lift against the upper track caused this to give way, whereupon the machine rose into the air with Mr. Maxim and his assistant, then toppled over on the soft earth, suffering some damage to its framework. Here the experiments were discontinued for lack of funds, having indeed demonstrated that a large weight can be carried in dynamic flight, but having proved little as to the feasibility of controlling an aëroplane in launching, in free flight, and in landing. Compared with the work of his contemporaries this achievement of Mr. Maxim was herculean, both in construction and expenditure, the cost being reported as nearly one hundred thousand dollars. It raised high hopes for aviation. It proved conclusively not only that a flying machine could be made to lift a pilot, but that it could carry hundreds of pounds additional weight. It still holds the world’s record for magnitude of machine and cargo. But it had two great defects; it was improperly balanced and it was inadequately powered; for, as Mr. Maxim says, “the quantity of water consumed was so large that the machine could not have remained in the air but a few minutes, even if I had had room to maneuver and learned the knack of balancing in the air.”[32] These defects, however, would soon be remedied by the work of others, and particularly by the costly experiments of the automobilists, who were rapidly developing a light gasoline motor suitable for aviation. The inventors thus far noticed had developed most of the important features of the present-day flying machines, but had not provided adequate mechanism for preserving a steady lateral balance. The present writer had proposed the combination of a double rudder and torsional wings to steer and control a flyer, and had published a paper setting forth its general principle and describing a specific device; but inventors had little need for a third rudder till they encountered the dangers of dynamic flight in gusty weather. The paper referred to was presented to the Third International Conference on Aërial Navigation, in August, 1893, under the title, _Stability of Aëroplanes and Flying Machines_, and was published with the proceedings of the conference.[33] It discusses mainly the question of automatic stability and steadiness; but recommends personal control during the experimental period. It concludes as follows: