(2) Individual diving problems including underwater reconnaissance, pipefitting, patching, welding, cutting with hydrogen torch and oxyelectric machine; survey of underwater conditions in mud, swift currents, and various tide actions; use of jetting nozzle and siphon. (3) Use of hand tools, air tools, machine tools, pumps, winches, and blacksmithing. (4) Rigging, beach gear, and hi-lines. (5) Elementary instruction and training in— (_a_) Diving-gear nomenclature. (_b_) Diving-gear maintenance. (_c_) Hazards of diving. (_d_) Physics of diving. (_e_) Skin diving. (_f_) Recompression tanks and tables. (_g_) Air compressors, air flasks, field expedients. (_h_) Signals and communications. (_i_) Ship construction. (_j_) Mooring and maneuvering. (_k_) Sketching. (_l_) Tactical military instruction. [Illustration: _1. Hand pump._ _2. Rubber sneakers._ _3. Air hose._ _4. Diver’s underwear._ _5. Expansion tank._ _6. Face mask._ _7. Weighted belt._ _Figure 43. No. 2 diving outfit set._] [Illustration: _Figure 44. Diver in No. 2 diving outfit set._] =c. Diesel engineer training.= This is advanced training for those men having previous Diesel experience. The operation, maintenance, and repair of Diesel engines are studied. =d. Seaman training.= The apprentice seaman is given a basic course in seamanship. It includes instruction in— (1) _Nautical terms._ All nautical terms and what they mean, including the parts of a ship and construction terms. (2) _Ground tackle and its use._ The various kinds of anchors and how they are used; rules for anchoring. (3) _Lifeboat seamanship._ Lifeboats and their handling, surf seamanship, the sea anchor, use of oil, helmsmanship. (4) _Safety at sea._ Avoiding accidents, keeping equipment shipshape, safeguarding against fire, fire-fighting and life-saving equipment, first aid. (5) _Marlinespike seamanship._ The common knots, how to make fast to a cleat, whipping, splicing, the care of rope, handling and use of lines. (6) _The compass._ Types of compasses, installation and care, boxing the compass, points and degrees, variation and deviation, compensating the compass. (7) _General._ General seaman duties and seaman watches. =e. Visual signal instruction.= The visual signal training should include: (1) International code flags. (2) Semaphore. (3) Flashing light signals. (4) The signal code. (5) Typical signals. (6) Special Navy signals. (7) Signaling Navy and Coast Guard vessels. (8) Special flags and pennants. (9) Pyrotechnics. =f. Degaussing school.= At the Navy degaussing school, complete degaussing of a ship is taught, including what equipment is required and how it is used. =g. Wartime radio procedure.= The wartime radio procedure is that procedure practiced by the Navy. It includes: (1) Ship-to-ship, ship-to-shore, and ship-to-plane radio instruction. (2) Call numbers and identification. (3) Codes. (4) Radio discipline.