Correct spelling for the English word "pneumin" is [njˈuːmɪn], [njˈuːmɪn], [n_j_ˈuː_m_ɪ_n] (IPA phonetic alphabet).
Methylene-creosote, an insoluble yellow powder without odor or taste, recommended in bronchitis and tuberculosis in doses of gr. 4-8 (0.25-0.5); it is obtained by the action of formaldehyde on creosote.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.