state authorities. The Marine Hospitals, as their name suggests, were hospitals constructed at key sea and river ports across the nation to provide health care for merchant marine sailors. Aside from the well-being of these sailors, the hospitals provided a key monitoring and gate-keeping function against pathogenic diseases. As immigration increased dramatically in the late 19th century, the Federal Government also took over the processing of immigrants from the individual states, beginning in 1891. The Marine Hospital Service was assigned the responsibility for the medical inspection of arriving immigrants at sites such as Ellis Island in New York Harbor. Commissioned officers played a major role in fulfilling the Service's commitment to prevent disease from entering the country. As the nation grew, the scope of Marine Hospital Service's duties grew to include domestic and foreign quarantine and other national public health functions. Over time, the hospitals of the service were also expanded to include research and prevention work as well as the care of patients. Aside from merchant seamen, members of the military, immigrants, Native Americans, other federal beneficiaries, and people affected by chronic and epidemic diseases found a source for health care in the MHS and its hospitals. In 1899, the Marine Hospital Service first formed internal divisions: the Division of Marine Hospitals and Relief, Division of Domestic (Interstate) Quarantine, Division of Insular and Foreign Quarantine and Immigration, Division of Personnel and Accounts, Division of Sanitary Reports and Statistics, Division of Scientific Research and Sanitation, and Miscellaneous Division, although there were minor name changes after this time. Transformation into Public Health Service In 1902, the Marine Hospital Service was renamed the "Public Health and Marine-Hospital Service." In 1912, as the emphasis of its responsibilities shifted from sailors to general public health, the name was changed again to the "Public Health Service" to encompass its diverse and changing mission. The Division of Hospitals, which contained the Marine Hospital system, became part of the Bureau of Medical Services in 1943, and was eventually renamed as a different Bureau of Medical Services within the Health Services Administration in 1973. Large new buildings were constructed for many Marine Hospitals in the 1920s and 1930s, and the system reached its peak of 30 hospitals in 1943. A wave of closings in 1944–1953 mainly targeted hospitals that had not been upgraded, and another wave during 1965–1970 closed the remaining hospitals at inland locations, leaving eight general