officers, 68

_Invincible_, H.M.S., 255

Isolation of mined areas, 159

JELLICOE, Sir John, 252

KING'S Messengers, 108

LANCE bombs, 91

Life-boat, work of, 222-223

Lighted barrage, 183

Lightning reveals U-boat, 260

_Lion_, H.M.S., after Jutland, 56, 254

Liverpool harbour mined-in, 209

Loss of ships, percentage of, 54, 55

Lowestoft harbour mined-in, 209

_Lusitania_, sinking of, 18

MANNING of British ships in past, 20

Mercantile fleets under convoy, 116

-- Marine, 122

-- shipping in danger zone, 209

Merchant ships, loss of, due to mines, 155

Methods of attacking submarines, 134-142

Mine barrages, 129, 139, 156, 179, 286

Mine-field, Christmas on, 192-200

Mine-fields, deep-laid, 139, 179-186

Mine-layers, 233-236

Mine nets, 39, 138

Mine-protection devices, 175-178

Mined areas, isolation of, 159

Minesweeping, 54, 121, 157, 178, 209, 293-300

Mine-laying from U-C boats, 152-153, 157

Mines destroyed by British Navy, 155, 158, 209

Mines, floating, 150

Mining School, Portsmouth, 163

M.L.'s. See under Motor Launches

Modified sweeps, 96-101

_Moewe_, German raider, 145

Monotony, effect of, 280

Moonlight, effect of on searchlights, 297-298

Moral effect of air raids, 295

Moray Firth, mine-field in, 161

Morning divisions in warships, 41

Motor launch flotillas, 36, 115, 134-136

Motor launches, Admiralty contract for, 57

Motor launches, arrival of, 38

-- construction of, 58-62

-- description of, 56

-- area patrolled by, 61

-- loss of, 62

-- in actions off Zeebrugge and Ostend, 62, 287

Mysteries of sea war, 264-272

-- of submarine hunting, 126-162

-- of German mine-laying, 143-156

-- of minesweeping, 157-178

Mystery ships, 96, 101

-- numbers employed, 96

NATIONAL Insurance, 125

Naval bases, 102-115

-- centres, 129

-- College, Greenwich, 35