I think a Philly Rev War museum would be the best source for authenticating this. Hosman brings up a good point about the language. I would also look at the capitalization, which was hit and miss in those days, but the general rule of thumb was to capitalize all important common nouns in addition to proper nouns. Which words are capitalized, as shown in your post? Although it wouldn't resolve the issue either way, it might give us a clue.