In 1828 he produced armillary sphere illustrating the heliocentric model of the geocentric i. The device and its use has created treatise Anweisung zum Gebrauch dieser Ringkugel (armillary-Sphäre).
In 1828 he produced armillary sphere illustrating the heliocentric model. For the device and its use, he created treatise "Anweisung zum Gebrauch dieser Ringkugel" (armillary-Sphäre).