05/05/1930
https://www.presidency.ucsb.edu...
"Leave of absence is granted, within statutory limitations, at the discretion of the President, acting through the Secretary of State."
"'Foreign Service officer' shall be deemed to denote permanent officers of the Foreign Service below the grade of minister."
"Whenever a Foreign Service officer becomes separated from the service, except for disability before reaching the age of retirement, or under section 33 of the act of February 23, 1931, the total amoun..."
"The Secretary of State is also authorized to grant to any officer or employee of the Foreign Service on account of personal illness or on account of exposure to a contagious disease which would render..."