The DL35 is an octal based audio output beam tetrode for use with dry batteries. This is no miniature valve so the probability is that the broadcast receivers that it was to be used with were large static pieces of equipment.
From the top of the dome the oval shape of the anode and outer grid can be seen. The inner grids are wound to be much closer to the filament.
The flying wires on the right are the filament springs. The spacing of the grids can be seen from the grid support rods that emerge through the top mica.
The pinch and connections to the valve. The latter would be assembled by hand in a series of jigs and then held in a final jig whilst the shaped wires from the pinch were spot welded to the electrodes. In the full size hi-res picture the filament wires clearly bend on the bottom mica and pass almost parallel through the control grid. Also the fine grid wires can be seen on the notched rods as they emerge below the anode.
The wide glass tube envelope is 30 mm in diameter and, excluding the IO base pins, is 72 mm tall.
References: Data-sheet, 1040 & 1043. Type DL35 was first introduced in 1946.