The VA40 is a photocell from Cintel. The photo-cathode looks to be deposited on the inside of the glass tube envelope. The brochure says that this photo-cell has a dual cathode.
The support on the left connects to a narrow flat electrode. The cup would have contained the active material that was ejected during manufacture.
The identification label. On the rear wall of the envelope can be seen the two cathodes with a clear vertical strip between.
The wire in the glass tube connects to the coating on the glass.
The wide glass tube envelope is 26 mm in diameter and, excluding the B4 base pins, is 67 mm tall.
Updated September 10, 2019. shape:wide.glass.tube construction:pinch type:photocell age:1930.1940 base:b4 pins:4 pin: