Analysis of information sources in references of the Wikipedia article "Hoffman Island" in English language version.
April 23, 1863, what is now known as the General Quarantine Act was passed, defining the quarantine establishment, authorizing its construction, creating the permanent office of Quarantine Commissioner, defining the duties and powers of the Commissioners and Health Officer, and establishing a general system of quarantine for the port. Additional powers were conferred by amendments made to this general act in 1864, 1865, 1866, and 1867, under which two small steamers were purchased; the property at Tompkinsville, Staten Island, known as the Marine Hospital Grounds, was sold; and the artificial islands in the lower bay were undertaken and afterward completed – Swinburne Island in 1860, and Hoffman Island in 1873.
