9 8 D O C U M E N T 8 7 O C T O B E R 1 9 2 5 Hence the change in vert. speed is the only remaining hazard. It generates elastic deformations of the frame, which, however, can be adequately compensated by the symmetrical arrangement, to first approximation. Horizontal accelerations: In my opinion the amplitude of the swing of the basket will come at most to 10 cm. That yields accelerations of , hence changes of g. They generate no forces for objects located at the center of oscillation. This has to be taken into account in the load distribution. If we assume a difference in radii of 1 m, then we have changes in acceleration of . A horizontal brass beam 50 cm in length suspended from one side suffers a relative change in length of . This deformation is at the acceptable limit. It is considerably diminished by the correct choice of supporting points. The mirror fixtures must be built very rigidly so that those accelerations don’t affect them by bending and, in addition, the 3 mirrors must be affixed identically. Vibrations and inclinations of the basket. The former are caused by the crew, the latter by ¢alteration² ex- pansion of the fill gas & by wind differences between the balloon & the tow line. To avoid this, my plan is: The tow line will be put out only at the end of the trip. (At night, this requires a certain amount of caution but as I intend to go upwards right away, there is no danger. Furthermore, I have the echo sounder in the form of a small trumpet. I am going to be traveling alone I have a pilot’s license.) The basket will be sus- pended loosely from the balloon, as is usual for teth- ered balloons. Two carrier rings are used for that & between the two, a so-called cone out of roping. A small metal ring forms its center. To this small ring I will attach a very small basket (paper basket), in which I am going to be standing. Since both baskets have diff[erent] periods, I can gently brake an eventual oscillation (insofar as it is not being damped by the bal- loon) by allowing a horizontal string that is in line with the large basket, to run be- tween two of my fingers. Thus, the large basket will be vibration free. g · 1 240 -------- - ⋅± 1 120 -------- - 1 12.120 ----------------g 1 1440 -----------g - 7.10 4– g = = ΔL L ------ - σ2 2E ------ - 1 3000 ----------- - 1 2.102 ------------ ⋅ 1 7.10–10 , = = =