The originals were photographed for NNP by John Graffeo and Nicole Fry as part of Entry-1 "General Correspondence." I adjusted the above images for improved readability. These are among the thousands of documents selected for eventual transcription. I have a larger size group made at NARA College Park, Md., covering a wide range of Mint, Treasury, and Secret Service materials.
PS: I think the company name at bottom of the Aetna letter refers to Valvoline Oil Co. (1866: Dr. John Ellis founded Valvoline in 1866 when he discovered the lubricating properties of distilled crude oil, formulating the world's first petroleum-based lubricant. Valvoline™ oil was officially trademarked in 1873.)