2 6 2 D O C U M E N T 3 2 8 A U G U S T 1 9 2 2 make do with a sole blow magnet, if the sphere with the water at +4° has a mini- mum weight of 50 gr., which then can rise to c. 120 gr. at c. 50°. The blow magnet in the sphere can be much smaller because the centering is considerably simplified it is similar to an inner tooth wheel against an outer tooth wheel I got a quite good centering already from a coil magnet of c. 3° iron thickness in the application I chose a ring coil drawn out to 20°. I chose 2 gyros but set the axes of the gyro caps vertically, after all, because the ties between the sphere and the gyros seem less doubtful in this arrangement I fear a rolling error could occur if I lay the bearings of the gyro-cap axes in the equator, because then the sphere is only attached by the springs to the gyros and the lower- lying weight of the two gyros will enable it to perform oscillations that are too close to the rhythm of the ship’s accelerations with the vertical arrangement there are no forces on a ship that could act rotationally on the sphere. Your suggestion about using two counter-rotating gyros as an artificial horizon is already familiar to me first, for the artificial horizon of airplanes, one gyro prob- ably suffices that has an appropriately long oscillation period, e.g., 15 minutes. The accuracy required is not great, approx. one degree. The situation is different for an artif. horizon for ships to substitute a sextant other ways will probably have to be chosen for this perhaps you suggestion would be best. I look forward to being able to consult with you about this next summer. When is your Albert arriving in Munich to matriculate? Hopefully we will already be there then we would like to accommodate him in our house upstairs I hope the housing office won’t scratch out this plan of ours. In any event, he will initially be living with us, a guestroom is here for him in any case, even if we should happen not to be here yet. We would like to be in Munich, depending on the weather, roughly around October 20th but he can come earlier as well we look for- ward to seeing him. Then in November I shall go to Kiel to have a look at how the new sphere is doing, and your Diogenes Tub, too, the rough shell of which should be ready by then. Here in Lautrach it still looks bad: painters, decorators, and masons dominate with some trouble we managed to wrest a very unlivable room from the workmen as a temporary refuge but now things are getting better by the day. It is so peaceful and quiet here you will enjoy it if you are yearning to escape from the Berlin hub- bub and lodge here in peaceful tranquillity. My wife and I send our best regards between households, yours, Anschütz-Kaempfe.