Take a good look at the top view. The photo shows that this is an eight-tube receiver, dependent on an external power unit. There is one RF and two IF stages. The final audio appears to be transformer coupled. Wiring, neatly done, appears to be buss with a liberal use of spaghetti insulation.
All parts appear to be of high quality.
The by-pass capacitors could well be mica, and it is very possible that this receiver, if unearthed today from some storage depot, would work immediately without servicing, and probably give a good account of itself by 1940s standards. The design is fundamental, without any expensive sheet-metal fabrication or surplus circuitry. This particular model appears to be in mint shape and was probably received at the National Company laboratories for evaluation either during the war or very shortly thereafter. The very professional photos are in with all the others done by Benj. Morse of Boston, and although these do not have his imprint on the back, they certainly appear to be his work.