 Nyora kupfuurira kweiyi ndima - Chikamu chitsva chaHaber chakanzi Pioneer Regiment 35. Pashure pokudzidziswa kwenguva pfupi muBerlin, Hahn, pamwe chete navafizikisi James Franck naGustav Hertz, vakatumirwazve kuFlanders kunotsvaka nzvimbo yokutanga kurwisa negasi. Haana kupupurira kudenha nokuti iye naFranck vakanga vari kunze vachisarudza nzvimbo nokuda kwedenho inotevera. Kuendeswa kuPoland, paHondo yeBolimówMusi wa12 June 1915, vakabudisa musanganiswa wegesi yechlorine nephosgene. Vamwe varwi veGermany vakanga vasingadi kufambira mberi apo gasi racho rakatanga kuputika, naizvozvo Hahn akavatungamirira kuyambuka nyika yomunhu. Akapupurira marwadzo orufu rwavaRussia avo vakanga vapiswa, uye akaedza pasina budiriro kumutsiridza vamwe namamasiki egasi. Akaendeswa kuBerlin somunhu ari kuedza magasi ane chepfu nemasikisi egasi. Pakuedza kwavo kunotevera musi wa7 Chikunguru, gasi racho rakarova zvakare pamitsetse yeGermany, uye Hertz akaiswa chepfu. Uyu mugove wakambovhiringidzwa nebasa raiitwa pamberi muFlanders uyezve muna 1916 nebasa rokuenda kuVerdun kunopinza magora akazadzwa nephosgene kuWestern Front. Ipapo zvakare akanga achitsvaka nzvimbo dzokurwiswa negasi pamativi ose maviri. Muna December 1916 akabatana neboka idzva revatungamiriri vegasi paMuzinda weHurumende. 