I finally got back to work on the Registry of Noteworthy Research in Pathology and today found some letters.
James Carroll was a Major in the Army who worked with Walter Reed on his yellow fever research. He volunteered to be bitten by a mosquito that had previously bitten three others who had yellow fever. He contracted the disease and several years later died of cardiac disease that was attributed to his bout of yellow fever.
Here's a letter from the President of the Carnegie Foundation for the Advancement of Teaching, petitioning a Congressman to grant a special pension to Carroll's widow.
And here is the Congressman's reply.
Maybe I'm missing something, but I thought being a Major in the Army meant you were in military service to your country.