D.

Danes, incursions of, 368, 369.

Danger of two wars at once, 36.

Dangers of auxiliary armies, 170.

Danube, Napoleon's passage of, 226. valley of, key of Southern Germany, 162.

Decisive direction, 328. moment of battle, 334. point at Bautzen, 187. point, how affected by arrangement of forces, 187. point of battle-field, 187. point of battle-field, how determined, 88, 186. points, 337. points, defiles as, 87. points of the theater of war, 85.

Deep columns, 356. at Waterloo, 359. masses, 298, 302. order, disadvantages of, 298.

Defeat, 68. of the French at Waterloo, causes of, 359.

Defense, in mountainous countries, 163. line of, important to an army of invasion, 99. line of, should be short, 98. of frontiers, 146. of intrenched camps and lines, 215. rivers, mountains, and defiles as eventual lines of, 96. second lines of, 147. should not be passive, 185. tactical, of Switzerland, 169. maxims for frontier, 148, 149.

Defensive armor for cavalry, 308. army has the advantage, when, 202. army, proper course for, 324. arrangements for battle, 201. battles, 179. best formation of infantry for, 298. cavalry in, 306. characteristics of infantry formation for, 297. in descents, duty of, 251. line of battle, heavy artillery in, 290.

Defensive movements, when advised, 124. -offensive war, 74. or offensive system, either may be employed, 185. the, in a level country, 164. war, 72, 73.

Defiles as decisive points, 87. as eventual lines of defense, 96. in retreats, 243.

Definitive lines, 103.

Dennewitz, Ney's error at, 130.

Deployed battalions in checkerwise order, 301. lines in two ranks, 294. lines, two, formation of infantry in, 292.

Depots, establishment of, on march, 262. command of, 263. lines of, 263. of supplies, 141. of supplies, general maxims, 143. secondary, 262, 263.

Descents, 248. cases where made, 250. difficulties of, 250. duty of defensive in, 251. effect of modern inventions on, 248. more extensive in ancient times, 248. precautions after landing, 252. rules for conducting, 251.

D'Estaing's fleet, 383.

Detached orders of Napoleon, 259. works, importance of, 154.

Detachments, field of operations of, should be large, 220. four kinds of, 217. great, 217, 219, 334. great, instances of, 221, 222. great, why made, 220, 221. multiplication of, must be avoided, 221. necessary when there is a double strategic front, 220. of Napoleon in 1805, 222. precise rules for, cannot be laid down, 222. requisites in officers of, 224. small, how useful, 224.

Detachment to form strategic reserve, illustration of, 219.

Détours, 197, 204.

Difficulty of applying theories in war, 269.

Diplomacy in invasions, 24.

Direction, lines of, their importance illustrated, 116. of lines of operations, 115.

Discipline, importance of, 42. importance of, in retreats, 242.

Distances in battle, calculation of, 334.

Distant expeditions, 169. invasions across extensive territories, 171. invasions, maxim for, 173. invasions to aid an ally, 170.

Distribution of troops in line of battle, 287.

Divergent lines, 103.

Duke of York's expedition to Dunkirk, 91. to Holland in 1799, 91.

Dumouriez, errors of, in 1792, 106, 107.

Dunkirk, expedition to, 91.

Duties of cavalry, 304. of staff officers, 254-256.

Duty of a general, 324. of statesmen in offensive wars, 17.

Diversions in zone of operations, when advantageous, 222.

Division, improper use of the term, 351.

Divisions, cavalry, of five regiments, 311. defects of system of, 278. remedied by Napoleon, 278. formation by, when preferable, 286. organization of, 279, 280. system of, 278.

Doctoroff, warning given to, in 1812, by Seslawin, 273.

Double line of operations, when applicable, 117. when necessary, 116. lines of operations, 102, 110. when advantageous, 123. lines to be avoided, 330. passages of rivers, 230. strategic front, 95. wars, 36. wars of Napoleon, 37.

Dragoons, 308. concentration of, by Emperor Nicholas, 309.

Drepanum, 363.

Dresden, 305. intrenched camp at, 155, 211. Napoleon's order of battle at, 198. victory at, 124.

Drissa, camp of, 155, 157.

Divergent lines, when advantageous, 118. operations, 126. retreats, when admissible, 239.

Diversions, 218. instances of, 218. when useful, 218.

E.

Eccentric lines, 237. retreat. Bulow's use of the term, 237.

Eccentric system, 126.

Echelon, order of battle by, 193.

Echelons, order in, 193. squares in, 297.

Ecnomos, victory of, 363.

Edward III. of England, 376.

Egypt, expedition of John of Brienne against, 374.

Ehrenbreitstein, 158.

Elchingen, Ney at, 182.

Elective governments, weakness of, 46.

Elevated points, advantage of, for observation, 276.

Elongated squares, 296, 297.

Employment of artillery, 315-318.

Encounters of cavalry against cavalry, 311.

Enemy, bodies of, near line of operations, 67. contempt for, 63. how dislodged, 188. how to drive from his position, 201, 202. should not be paid to leave a country, 242.

Enemy's movements, importance of knowing, 268.

England controls the sea, 173. invasion of, by Sweyn, 370. projected invasion of, by Napoleon, 249, 250, 386.

England's attack on Washington in 1814, 385.

English and French expedition to China, 389.

English, descents of, on France, 376. expedition against Napoleon in 1815, 385. expedition in 1762 against Havana, 382. maritime expeditions, 384-390. squares at Waterloo, 294.

Enthusiasm, importance of, 41. not military spirit, 62.

Epaminondas, 190.

Error of Napoleon in campaign of 1812, 172.

Error of the allies in 1793, 107, 108.

Errors in strategy, 91.

Essential bases of military policy, 49.

Essling, 192, 193, 200, 350. Napoleon at, 158. Napoleon's order of battle at, 198. order of battle at, 192, 193.

Eugene at Turin, 153. march of, 141.

Eventual bases, 84. lines of defense, 96.

Expediency, wars of, 18.

Expedition of Prince Koudacheff, 273. to the Crimea, details of, 387-389.

Expeditions, assistance of fleets in, 174. distant, 169. marine, in modern times, 249. maritime, 361-390. of the ancients, 248. of the Middle Ages, 171.

## partly on land, partly by sea, 173.

Extended movements, when dangerous, 204.

Exterior lines of operations, 102.

Extermination, wars of, 34.

Eylau, 305, 306, 318, 352. French armament at, 47. Napoleon's march on, 94. Napoleon's order of battle at, 198. Russian artillery reserve at, 289. Russian order at, 295.

F.

Famous retreats, instances of, 233.

Field, strategic, of 1806, 113.

Field-works, directions for attack of, 211, 212. instances of well-arranged assaults on, 212.

Final reserves, 203.

Financial considerations, 50.

Fire-arms, influence of improvements in, on war, 347, 355, 359.

Fire-signals, how used, 276.

Flank attack, 203. attack, cavalry, 310. charges of cavalry, 307. marches, 139, 140. marches, where inadmissible, 140. tactical maneuver by, 140.

Flanks of companies, movement by, 300, 301. protection of, in tactical positions, 182.

Fleets, assistance of, in expeditions, 174.

Fleurus, 136, 193, 200. balloons used at, 275. order of battle at, 192.

Foot-artillery in line of battle, 289. in the offensive, 316.

Forests, advantages of, in retreats, 183.

Formation by divisions, when preferable, 286. for attack at Turin, 213. for battle in small columns, 350. for battle, Napoleon's system, 278, 279. for battle often determined by size of army, 285. for battle, Prussian and Austrian system, 354. for close attack, 301. of infantry for attack, five methods of, 292. in two ranks, 356. of troops for battle, 347-350.

Formations of cavalry, 309-311. of lines of battle for two infantry corps, 282-284. various, for infantry, 285.

Fortification of Coblentz, 157, 158.

Fortifications, remark upon, 151.

Fortified camps, 154. places, attack of, 210. places on the sea-coast, importance of, 152. places, when a misfortune, 152.

Fortresses at Mayence, 150. greatest advantages of, 150. large, when preferable, 150. number and position of, 149. of France and Austria, 149. on frontiers, 148. relation of, to strategy, 148, 150.

Forts in a mountainous country, 151. purposes of, 146.

Fossano, battle of, 168.

Four-rank formation of infantry, 291.

France adapted to parallel retreats, 240. coalition against, in 1793, 37. course and error of, in 1792, 105. fortresses of, 149. intention of, when declaring war in 1792, 105. invasions of, by the English, 376.

Francis I., passage of the Alps by, 168.

Frederick the Great, 36, 37. at Leuthen, 229. at Prague, 205. at Torgau, 206. commissariat of, 142. defensive-offensive operations of, 74. maneuver of, at Leuthen, 141. military genius of, 16.

Frederick II., Crusade of, 374.

French and English expedition to China, 389.

French armies in the Revolution, 135. armies, situation of, in 1800, 112. at Bautzen, 196. at Fleurus, why successful, 193. at Waterloo, 196. capture of Vera Cruz by, in 1838, 386. causes of defeat of, at Waterloo, 359. cavalry, 313. columns at Waterloo, 351. defeat of, at Stockach, 111. descent on Algiers in 1830, 386. errors in 1795, 136. expedition to Syria, 390. in Bohemia in 1742, 171. invasions of 1766 and 1795, 120.

French, maritime efforts of, during American Revolution, 383. operations in Italy, 112. operations of, at close of 1793, 331-333. operations of, in 1794, 108. order at Essling and Fleurus, 200. order at Minden, 278. plan in 1799, error of, 110. Revolution, 26-28. Revolution, armies of, how subsisted, 142. Revolution, course of Austria in, 106. Revolution, course of Prussia in, 105, 106. Revolution, interest of Austria in, 105. Revolution, lines of operations in the wars of, 104. Revolution, relation of Italy to, 104. Revolution, relation of Prussia and Austria to, 104. Revolution, theater of operations in, 104. Revolution, zones of operations in, 105.

Frontier defenses, maxims for, 148, 149. when a permanent line of defense, 96.

Frontiers, defense of, 146. disadvantage of fortresses on, 148. how to be fortified, 152. mountains as, 146. rivers as, 147.

Front of operations, 330, 338. of operations, extent of, 98. of operations, how varied, 93. strategic, change of, 94. strategic, not to be too extended, 98.

Fronts of operations, 92.

Fronts, strategic, 92.

Fundamental principle of war, 66. maxims of, 70. principles for employment of troops, 328.

G.

Gallop, when best for cavalry charge, 306, 307.

General advanced guard, how composed, 262. cavalry charge, 305.

General, essential qualities of a, 55. importance of a skillful, 43. one of the greatest talents of, 74. qualities of a skillful, 334. what constitutes a, 327.

General principle of war, manner of applying, 175. staff, employment of, in time of peace, 49. staff, usefulness of, 57.

Genoa, panic at siege of, 64.

Geography, military, 39.

Geographical objective points, 88.

Germanicus, expedition of, 366.

Girondists, 26, 37.

Gosa, French charge on, 305.

Governments, elective, weakness of, 46. should not be unprepared for war, 46.

Grand tactics, 69, 70, 178. principles of, 360.

Great detachments, 217, 219, 334. instances of, 221, 222. why made, 220, 221.

Grouchy, 127.

Guard, advanced, 261, 262. in battle, 288, 289. in unexpected battles, 208.

Gunpowder, effect of invention of, on distant invasions, 171.

Gustavus Adolphus, expedition of, 375.

H.

Half-deep order, infantry-formation, 295. attacks in, 302.

Halts and departures in retreats, hours of, 236.

Halts in retreats to relieve rear-guards, 236.

Hannibal at Cannæ, 191. at Zama, 179.

Harold, 370, 371.

Head-quarters of the army, when the most important point, 107.

Heights to be secured in mountainous countries, 167.

Hengist, 367.

Henry V. of England, descents of, on France, 376.

Hoche's expedition to Ireland, 383.

Hochkirch, 303. surprise of, 209.

Hohenfriedberg, 305.

Hohenlinden, 183, 206.

Holland, expedition to, 91.

Horse-artillery in line of battle, 289. in the offensive, 316.

Houchard, 333.

Hougoumont, 303.

Hungary, strategic character of the mountains of, 161.

Hypotheses as to the enemy's movements, 270.

Hypotheses of the author in 1806, 271. how events justified them, 272.