Here is some information below. Also in question about Coast Artillery during WW1 they have been around for very long time and even so during WW2 they protected coastal areas, waterways and boarders. I think that it meant State and not Slay. He may have been in the New York State Coast Artillery Corps (CAC).
Dear Mr. McDonough,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog and located and Registers of Enlistments in the United States Army, 1798 - 1914 (M233) in the Records of the Adjutant General's Office, 1762 - 1917 (Record Group 94) but were unable to locate a listing for him.
If he served at a later date, there may be an Official Military Personnel File (OMPF). OMPFs and individual medical reports for enlisted men of the U.S. Army who were separated from the service after October 1912 and before 1959 are in the custody of NARA's National Personnel Records Center (NPRC) in St. Louis. In many cases where personnel records were destroyed in the 1973 fire, proof of service can be provided from other records such as morning reports, payrolls, and military orders, and a certificate of military service will be issued. Please complete a GSA Standard Form 180 and mail it to NARA's National Personnel Records Center, (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002. If there is any information requested by the form that you do not know, you may omit it or provide estimates (such as for dates), but the more information you provide, the easier it will be to locate the correct file if it survived the fire. For more information see Official Military Personnel Files (OMPF), Archival Records Requests.
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