It was unusual in having wings which could independently adjust their angles of attack, a feature intended to increase the energy acquired from gusts of wind.
An early glider of this type had been built by Erich Offermann before World War I and some theoretical work done by Albert Betz and, independently, R. Knoller, began to reach an understanding of how a plunging airfoil could generate thrust (the Knoller-Betz effect).
The wing was largely fabric covered but from the spar forward it was plywood skinned around the leading edge on the upper side, though the ply did not extend as far aft on the underside.
[1] The fuselage of the Doris had a wooden frame girder structure with a rectangular cross section, tapering aft to a horizontal wedge.
The angles of incidence were adjusted from the control column via pushrods, sideways movement rotating the wings in opposite directions to roll.
The high aspect ratio, all-moving tailplane was nearly rectangular in plan apart from angled tips and was fabric covered behind its leading edge.
The Doris was a short aircraft and its vertical tail was therefore large, with a quadrant shaped fin and a near rectangular rudder which had a small cut-away at its base for tailplane movement.
These were fixed to the fuselage at the nose and mounted on the ends of a pair of transverse, arched ash brackets on rubber shock absorbers.