PUBLIC LAWS-CH. 149-MAY 25, 1939 Hydrographic sur- veys. Proviso. Group IV (b) em- ployees. Organizing, recruit- ing, etc. 52 Stat. 1175; 49 Stat. 156. 34 U. S. C., Supp. IV, 6§ 852-853i, 842- 848. Naval and Marine Corps Reserve, avia- tion activities. Group IV (b) em- ployees. Provisos. Drills, limitation. Reserve officers per- forming active duty. Pay, allowances, etc., restriction. Pay of professors, etc. OCEAN AND LAKE SURVEYS, NAVY For hydrographic surveys, including the pay of the necessary hydrographic surveyors, cartographic draftsmen, and recorders, and for the purchase of nautical books, charts, and sailing directions, $80,000: Provided, That the sum to be paid out of this appropria- tion for employees assigned to group IV (b) and those performing similar services carried under native and alien schedules in the Schedule of Wages for Civil Employees in the Field Service of the Navy Department shall not exceed $34,000. NAVAL RESERVE For all expenses not otherwise provided for, authorized by the "Naval Reserve Act of 1938", and the Act approved April 15, 1935 (49 Stat. 156), in connection with organizing, administering, recruit- ing, instructing, training, and drilling the Naval Reserve, including the designing, purchasing, and engraving of medals and trophies; medical supplies and equipment; purchase, maintenance, and opera- tion of ambulances; aviation materiel, equipment, and fuel in connec- tion with the aviation activities of the Naval and Marine Corps Reserve; maintenance and operation of floating equipment; and rental, maintenance, and operation of such shore stations as may be required in connection with Naval Reserve activities, $9,937,205, of which amount not more than $7,222,615 shall be available, in addi- tion to other appropriations, for and on account of Naval and Marine Corps Reserve aviation; not more than $2,714,590 shall be available, in addition to other appropriations, for all other Naval Reserve activities; and not more than $81,000 shall be available for employees assigned to group IV (b) and those performing similar services car- ried under native and alien schedules in the Schedule of Wages for Civil Employees in the Field Service of the Navy Department: Pro- vided, That no part of any of the foregoing amounts shall be avail- able for the performance of more than forty-eight drills per annum or other equivalent instruction or duty or appropriate duties: Pro- vided further, That, except in time of war or during the existence of a national emergency declared by the President, no appropriation contained in this Act shall be available to pay more than twenty officers of the Naval Reserve and four officers of the Marine Corps Reserve above the grade of lieutenant or captain, respectively, the pay and allowances of their grade for the performance of active duty other than the performance of drills or other equivalent instruction or duty, or appropriate duties and the performance of fifteen days' active training duty, and other officers above such grades employed on such class of active duty (not to exceed four months in any calendar year) shall not be entitled to be paid a greater rate of pay and allowances than authorized by law for a lieutenant of the Navy or a captain of the Marine Corps entitled to not exceeding ten years' longevity pay: Provided further, That no appropriation made in this Act shall be available for pay, allowances, travel, or other expenses of any officer or enlisted men of the Naval or Marine Corps Reserve who may be drawing a pension, disability allowance, dis- ability compensation, or retired pay from the Government of the United States, and "retired pay" as here used shall not include the pay of members of the Fleet Reserve, Fleet Marine Corps Reserve, or members on the honorary retired list of such Reserve forces. NAVAL ACADEMY Pay, Naval Academy: For pay of professors and instructors, including one professor as librarian, and such amounts as may be 762 [53 STAT.