W AR D E P ARTM E N T , D ocum ent o C h ie o S ta 017206 f th e f f ff . AR D E P A RT M E N T W , F F I C E OF T H E H I E F OF TAF F O C S , lVashin n un 1 1 to J e 9 2 . g , M a m M inin to 1 9 1 2 This nual for S ub arine g , revised , is approved and published for the confidential information and f guidance of the Army o the U nited S tates . U nder no cir cumstances shall its conte nts be divulged to persons not in a r a a the milit ry o n val service o f the U nited S t tes . B y order of the Secretary of War : H A T W M . R E R C , M o ner l A in ie o S ta a r Ge a c C h . j , t g f f /f 3 C O N T E N T S . efinit ons and eneral r n es D i g p i cipl . M ateriel of th e system L oadi ng - room d uties L o at n stri tion b ox a n m t e a e mark c i g di bu , l yi g ul ipl c bl ing out mine fi eld Assembling and planting mi nes Test of mines and apparatus Taking up mi nes Th e mine command A E N I XE PP D S . E xplosives Oil engine and g enerator S torage b atter y S ubmarine - mine cable C are and preservati on of m até r ie l I nstr uctions for masters of mine planters M anual for small b oats S upply list H A TE R C P I . DEF N T N S AND E E RA E I I IO G N L PRIN CIPL S . A submarine mine consists of an explosive ch arge inclosed - e in a water tight case , and a firing device , the whol intended to be submerged in a w aterw ay which it is desired to close ’ an m ss against the passage of ene y s ve els . ' With respect to the position of the case containing the ex m m ar e a and plosive , sub arine ines of two cl sses , buoyant ground . a m In the buoy nt ine , the case contains the explosive and and of a the firing device , has such excess buoy ncy that it would float were it not held below the surface by a mooring m rope and an anchor . The sub ergence is such that while m a the ine would be struck by the hull of a p ssing vessel , it is s a not o near the surf ce as to be seen . B uoyant mines m ay be planted and operated successfully 1 50 T in water feet deep . hey should not , in general , be used a where the depth of w ter is less than 2 0 feet . m a the In the ground ine , the c se contains explosive and c the firing devi e , and is heavier than the displaced water ; m and it therefore rests upon the botto requires no anchor . Ground mines ar e not used where the depth of water exceeds 35 feet . to m a m m ma With respect the e ns used to fire the , ines y be m a classed as echanic l and electrical . E tw o a a s lectrical mines are , in turn , of gener l cl sse , con — tr ollable in which the firing device is under control after — the mine has been fixed in position ; and noncontrollable in which no such control is had . M echanical and noncontroll able electrical mines are in to a tended be fired only by the blow of a p ssing vessel . W h en once in position they are dangerous alike to friend R E G 8 SUBMA IN MININ . m s ma a ma and foe , while controllable ine y inst ntly be de safe for friendly vessels or as quickly m ade d angerous to vessels m of the ene y . Controllable electrical mines are arranged so as to give a m signal to the Operator when they ar e struck . They ay be to m m set fire auto atically wh en struck or ta pered with , or ma a a y be fired at the will of the oper tor . In the latter c se m a d a the firing y be elayed , in which case the oper tor fires the mine some short interval afte r the signal indicates that c e s it has been struck ; or by observation , in which as he fire it afte r the position - finding system shows that the vessel has m ’ co e within the mine s destructive radius. L C A TI N F M I N E O O O S . Th e considerations involved in the location of mines are of two a a a and . general classes , t ctic l loc l Tactical considerations deal with the position o f mines L with reference to the other defenses . ocal considerations a a de l with the width and depth of the ch nnel , the swiftness im of the current , the variation of the tide , and the relative a o f port nce the harbor . Wh ere ordinary ship channels ar e unobstructed it is pos m sible for odern battleships , with their high speed and m a in heavy ar or , to run by shore batteries , at le st the night or during a fog ; hence the defense of such channels should not be left to guns alone . On m ar e the other hand , where ines unprotected by the fire of shore batteries it is possible for an enemy to remove or disable them . T m m herefore guns and ines , the two ele ents of the fixed of a m a defenses a h rbor , are utu lly dependent , and when the location o f one has been decided upon th at of the other must conform thereto . Within th e z one between and yards o f th e main a defense the fire of he vy guns is destructive for warships , yet the l atter ar e at such a distance that their rapid - fi r e guns a will be of little effect against the b tteries . M R E G SUB A IN MININ . 9 M at a ar e oreover , y rds vessels just beyond the inner limit of mortar fire . s If possible , therefore , hostile vessels should be held in thi a f m zone by some obstacle . Such obst cle is af orded by a ine field . a On the other hand , attacks upon mine field are most a th e m liable to be made by sm ll boats at night . If ine field at too a m a be gre t a distance fro the defenses , these bo ts will m not . be revealed by the mine searchlights Further ore , for protection against such attacks , the defense relies upon - rapid fir e guns of relatively limited range . D ue to the above considerations the outermost mines are usu ally pl aced be tween and yards from the main defense . a be a m a a a In gener l , there should in e ch in ch nnel at le st s m three line of ines . M E N T F I N E Y TE M E LE S O A M S S . The elements of a mine system are 1 Th e minin c sem e m . g a at , consisting typically of four roo s 1 m a ( ) The operating roo , cont ining the power panel and the e 9 m th e en op rating boards ; ( ) the engine roo , containing and 3 m gine the generator ; ( ) the battery roo , containing the storage battery ; and (4 ) the sleeping room for the personnel . h mu cab es 1 2 . T e e 7 9 m ltipl l , and conductor , leading fro a m the c se ate out to the distribution boxes , one of which is m in the center and rear of each group of ines . Th s n e- conducto c b es a a t 3. e o i gl r a l , r di ting the front from ea to mi the distribution boxes , one l ding each ne . 4 Th e mines 1 9 . , in groups of or less , extending across the to d m 1 00 waterway be defen ed , planted approxi ately feet ap art and anchored so as to have a submergence of about 1 0 Th m 3 . e 1 2 . feet at low water groups are nu bered , , , etc , from left to right of the observer stationed in rear of the m a ar e m d m line , and the ines in e ch group nu bere si ilarly , :1 . 1 0 1 9 n No being on the left , No in the center , and No . o the right . R E IN G 1 0 SUBMA IN M IN . Th e groups composing a line of buoyant mines are not e a a a usually plant d in prolong tion of e ch other , but with l a S pace for the passage of friendly vesse s , and lso for the movement of the planter when at work upon adj acent m groups .