Passage: Orphaned as a child, Hartleben was brought up by his grandfather in Hanover.  Among his youthful acquaintances there were Karl Henckel, Arthur Gutheil and the future industrialist and politician Alfred Hugenberg and together they published a volume of poetry Quartett in 1886.  After completing his schooling in Celle in 1886 he went to study law, first in Leipzig, where he got to know Hermann Conradi and Adolf Bartels, and later in Berlin.  He studied for the civil service in Stolberg (Harz) and in Magdeburg.  Giving up his legal studies, he returned to Berlin where he lived as a freelance writer, eventually moving to Munich in 1901.  After the death of his grandfather in 1893, Hartleben inherited 80,000 marks and on 2 December married his lifelong companion, ex-waitress “little mop” Selma Hesse.

Question: Mention two youthful acquaintances of Hartleben?
Karl Henckel, Arthur Gutheil