 Complete the following phrase:  After his return to his homeland, he was a longtime teacher between 1859 and 1880, intermittently at the Artillery School, and served three times 18651868, 18741875, JuneNovember 1880 as its Chief. In 1870 now with the rank of major he was again in the Prussian General Staff, this time as an observer of the fighting in the Franco-Prussian War. He witnessed the sieges of Metz and 