“…The latter effect predominates if nickel is the catalyst. Thus, Willstátter, Seitz, and v. Braun (406) found that with a nickel catalyst at 225°C. no octahydroindole was formed, but that continued hydrogenation past the dihydro stage yielded l-ethyl-2-aminocyclohexane, which v. Braun, Bayer, and Blessing (54) had erroneously thought to be octahydroindole.…”