W H A T Z I T ?

10/3/07 - Kees Kort

It is the de Marçay C.1, a French prototype single-seat fighter (hence the designation C = Chasseur) which appeared just after WW1 early in 1919. The factory, owned by Edmond de Marçay, produced SPAD fighters under license during the war, probably explaining its resemblance in the C 1. Your picture shows the machine on the military French testing field at Villacoublay while it was there for official trials. The spinner of the machine is here removed.
10/3/07 - Roger Finnerty

A French DeMarcay 2C.1 of 1919. The same picture is in French Aircraft of the First World War.
10/16/07 - Jack Erickson

The de Marcay C.1 is French from 1918.