The work on this small engine was pushed forward very rapidly, so that within a short time it was sufficiently complete to allow some power tests to be made with it. In the first of these tests the attempt was made to measure the power by means of the Prony brake, but as the engine had no fly wheel the fluctuations in speed during each revolution were so great as to make it impossible to obtain readings of any value. When it was attempted to remedy this by putting a fly wheel on either side of the crank shaft of the engine, it was found that the sudden starting of the engine caused such severe strains in the crank shaft, which had been built strong enough for driving the propellers but not for suddenly starting fly wheels having considerable inertia, as to make it unsafe to continue the use of fly wheels. As without them the Prony brake could not be used, it was decided to build a small water-absorption dynamometer on the same principle as the larger ones which were under construction for the large engine. As this larger dynamometer has already been described, it is only necessary to add that the small one consisted of twelve rotating plates and twelve stator plates twelve inches in diameter. In order to avoid the construction of a special and elaborate testing frame for mounting the engine and the dynamometer exactly in line with each other, it was attempted to connect them by means of a universal joint. This “short cut” also proved the “long way around.” The strains set up in the universal joint by the sudden starting of [p229] the engine caused so much trouble on account of the inertia of the rotating plates of the dynamometer that the time lost in keeping the universal joint in working order during the tests more than counterbalanced the extra time which would have been required to construct a special wooden frame on which the dynamometer and engine could have been mounted in line with each other so that the crank shaft of the engine could have been directly connected to the shaft of the dynamometer.