The principal officers who have to do with currency administration are the director of the mint and the comptroller of the currency. _The Director of the Mint_ has general supervision of the administration of the coinage laws and the management of the coinage and assay offices.[89] _The Comptroller of the Currency_ exercises supervision over the national banks. It is his duty to see that national banks are properly organized, that the capital stock is fully subscribed and paid in, that the necessary amount of United States bonds have been duly deposited with the government to secure the circulation of their notes, and that all national banks are properly examined from time to time. He also has important duties in connection with the management of the federal reserve banks. He has charge of the issue of national bank notes and (under the supervision the Federal Reserve Board) of Federal reserve notes. [89] For a list of the mints and assay offices, see pp. 228-229. Among the bureaus of the treasury department which have no direct relation to the public finances the most important is the _Public Health Service_, which is under the direction of a surgeon general who is charged with the supervision of the national quarantine stations and of hospitals for the relief of sick and disabled seamen, and discharged soldiers, sailors, and marines. He calls conferences of all state health boards. He is authorized to adopt regulations to prevent the introduction and spread of contagious diseases, and it is his duty to supervise the medical examination of immigrants seeking admission to the United States. _The Coast Guard_, as organized in 1915, is charged with the duties of the former _life-saving service_ and the _revenue cutter service_. It renders assistance to persons and vessels in distress, patrols the coast for the purpose of preventing violations of the customs laws, and enforces the laws relating to quarantine, navigation, protection of the game, fishery, and seal industries, etc. It constitutes a part of the military forces and is under the treasury department in time of peace and under the navy department in time of war. _The Supervising Architect_ is charged with the selection and purchase of sites for government buildings, such as federal courthouses, post-office buildings, customhouses, mints, etc.; with the preparation of plans and specifications and the awarding of contracts for such buildings. _The Bureau of Engraving and Printing_ is charged with the duty of engraving and printing all government securities, including United States notes, bonds, certificates, national bank notes, federal reserve notes, internal revenue, customs, and postage stamps, treasury drafts, etc. _The Secret Service Division_ is a body of detective agents employed to detect frauds and crimes against the government, such as counterfeiting or espionage. Some of the force are also employed in guarding the President.