Bruno,
Your helmet is interesting! The name TARCHER does not bring any results, no such name in the whole german lists. I presume this was a guy who wore this helmet during peace time, long time before the mobilisation.
But......Interestingly, your helmet has been assembled from a lot of old parts to be given in the urgence to a reservist or a Landwehrmann at the mobilisation. It has the emblem of Saxe-Weimar-Eisenach, but it is the wrong emblem for this old helmet of the JR32 (Meiningen) which formed august 1914 the I/RJR71 in Meiningen. I am sure that the stamp that you can not read is: I.B R.J.R.71 The emblem should have the laurel leaves on both sides of the saxon center (Saxe-Altenburg and Saxe-Coburg-Gotha). But as this helmet has been assembled in this period of helmet shortage, no problem for me about its 100% authenticity for this kind of helmets of the small duchies.
It is perfectly matching with the second name in the helmet: Gefreiter RÖHNER, born Juli 1882, from the first company. I tracked him in the lists: Gefreiter der Landwehr August RÖHNER from the 1. company RJR71 (IB), missing during the fights between the 8 and 24.9.1914 at Ormoy, Droiselles, Lombray, Cuts, Nouvron and Morsain (Aisne).
http://des.genealogy.net/search/show/637620
But a second publication of 1918 is telling that this guy died in captivity:
http://des.genealogy.net/search/show/8125000
And we find him at the Red Cross. It is told there, that he was wounded and then missed on the 13.9.14 during the fight at Channy and Nouvron near Reims:
https://grandeguerre.icrc.org/fr/File/Details/311935/1/2/
Obviously he has then been taken prisonner and died a few days later in captivity.
Philippe
:wink: