It always adds to the story of a particular instrument when the purchase documents are available. Here is another great example.

Serial number 73316 was stamped on September 22, 1939 and cleared final inspection on December 4 that year.

As can be seen from the documents below this guitar was sold by Wilson Music Co. who was a Martin dealers in Oshkosh WI. This guitar was ordered by Wilson Music on November 22, 1939 and was certainly shipped on December 4 or very shortly thereafter. This guitar was in stock at Wilson Music for the better part of a year before it sold on October 26, 1940.

The tuners are Grover G-98 pointed plate machines.

Style 18 features:

Back and sides: Mahogany

Top: Red spruce (Adirondack)

Purfling: Lines

Binding: Tortoiseshell celluloid

Back stripe: None

Other period features:

Rear X-bracing

Ebony fingerboard

Ebony belly bridge

Steel T-bar neck reinforcement

1-11/16" neck width at nut

Tortoiseshell celluloid pick guard

Dot fingerboard inlays

Decal on front of headstock

No C. F. Martin stamp on back of headstock

Style stamp