The image here is a print is titled "Sketches is the New York Quarantine Establishment" it was published in "Harper's Weekly" in October of 1887.
I was browsing a list of minor islands around New York. To the west I found other islands in the Raritan and lower New York Bay: Swinburne, Skeleton Hill, and Hoffman Island. Hoffman and Swinburne were man-made islands, created to quarantine immigrants that were discovered at Ellis Island to be carrying contagious diseases, especially Smallpox. the islands were made with dredged sand in the 1860s, and closed in the 1930s. My research indicates that their facilities were razed sometime in the 1960s. Today the properties are owned by the National Parks Service and are off limits to we homosapiens. More here.
So how does this come back around to radio? Hoffman Island had a second life after the quarantine gig as the first U. S. maritime service training station. They opened on September 7th 1938. They turned out maritime radio operators and other seamen. The first Seamen who appeared on the island were members of recruits from the C.C.C. (Civilian Conservation Corps).
I know little of the radio school itself. I know it operated for only about one year. The school was operated by the United States Maritime Service in New York Harbor around the years 1944 and 1945, and that it cooperated with the Gallup Island station, and the U.S. Maritime Service radio school at Huntington, Long Island. Mast Magazine published a short article that's online here.
The Hoffman Island Radio Association has about 165 members consisting primarily of graduates, instructors and staff from the Hoffman Island Radio School. HIRA describes itself as mainly a social organization. You can see island pictures here.