ship of the admiral commanding in chief is posted as usual in the centre of his fleet, unless he should quit that position and take post at the head of either squadron, the better to superintend and direct the execution of his plans of operation. In so doing, be it observed, he ought not to supersede the divisional officer commanding the squadron to which he may repair; for, in no case, should the commander-in-chief be burthened with the details of any divisional movements. The position which the flag-ship before occupied is to be supplied by a ship of the line placed behind the admiral's flag-ship, and bearing the same number; this is called the duplicate or substitute vessel, being a substitute for that of the admiral, and distinguished by the divisional flag of the squadron to which she belongs."

109. A fleet steaming in divisions, each formed in a double column of ships in lines of bearing, having its advanced posts of steam sloops, with supports of steam frigates, considerably in advance, and a reserve of swift ships of the line (Fig. 8, p. 92), possesses great military strength, from the reciprocal defence which the ships afford to each other, as shown by the lines of fire (figs. 13 and 14, p. 98), and could not be broken in upon by an enemy without severe loss and much danger to himself. This order of steaming is moreover admirably calculated to take immediate advantage of any error or false movement on the part of the enemy, by the prompt convertibility of the columns severally into lines en échelon, and the formation of the whole into order of battle in any direction.

Line may be formed in the direction A B (fig. 8), by bringing up the heads of the three columns, l, n, p, into that alignment, and then forming them into lines on their respective centre ships; or, should an enemy appear on the starboard or N.E. quarter, the left column (1) should be brought up to m and the whole form échelon

This is now the French practice.-(Batailles de Mer, par l'Amiral Comte Bouet Willaumetz, p. 421; fig. 48, p. 423.) It would be preferable to call up a line-of-battle ship from the reserve, to serve as the substitute ship.

of divisions in line, by moving up the port branches of each double column into line with their respective starboard branches, and so be in a position either to

form line in the direction C D, or by changing the courses of ships to the N.E., form line to the right in the direction E F. In like manner the fleet may form line to the left, or port, should the appearance of the enemy be in that quarter.

Fig. 9.

110. Columns of ships in performing evolutions to be followed by formations on a front line, as with armies, should have little depth, in order that the line may be formed as speedily as possible. Now columns of ships ranged in line ahead cannot be closer in file than, at least, one cable's length (720 feet), without the risk of getting foul of one another; and assuming each ship to be 250 feet long, a squad

Fig. 10.

ron of 7 ships in a double column, line ahead formed on a centre ship, as in fig. 9, would occupy in depth above 1050 yards; while the same number of ships, if formed in a double column, in lines of bearing, as in fig. 10, would only extend in depth 330 yards.

111. The order of sailing in line of bearing is, perhaps, by the reciprocal defence which the ships afford each other, that alone which can properly be considered as founded on sound tactical principles. But this order is, with sailing ships, restricted to particular cases, being dependent on the wind, and is with difficulty retained; while, by the agency of steam, the oblique order and échelon formations are at all times possible and easily put in practice, and should be generally used not only in orders of movement, but in

* Lines of bearing, when the ships are disposed en échelon, are commonly called by seamen bow and quarter lines; because, by the obliquity of the ships to the general line of their direction, the bow and the quarter of each ship are brought respectively opposite the quarter and bow of that which is nearest

to it.

b"L'ordre oblique est l'ordre de bataille le plus usité, le plus 'savant, et le plus susceptible de combinaisons.”—(Guibert, vol. ii. p. 73.) This is said of armies on land; and the same may be predicated of steam fleets in oblique and échelon formations at sea.-(See Batailles de Terre et de Mer, by M. Bouet de Willaumetz, p. 425.)

anchoring the ships of a fleet in line of bearing athwart the wind or the tide, so that no ship can drive on the hawse of another. Those orders, and the movements arising from them, will therefore, no doubt, be henceforth generally used in naval warfare between steam fleets.

112. In the tactics of sailing fleets the lines of bearing were confined to the two close-hauled lines, in either of which the ships might be ranged in line ahead, or en échelon, on the same tack, at six points from the wind. Thus the ships might be in line ahead, as at A B (fig. 11), or on the same tack (starboard) in the

line of bearing A C; or they might be in line ahead, as at DE, or on the same tack (port) in the line of bearing D F. From either of these positions the whole may be formed in order of battle on either tack, by causing the ships en échelon, A C, D F, to form line, in rear of A B or DE.

But no movement to windward of the close-hauled lines could be made by sailing ships, except by the slow process of tacking and fetching-up against the wind; therefore, within the space contained between the two close-hauled lines, forming with each other an angle equal to 12 points of the compass or 135°, sailing ships have not the power of making any direct attack upon, or any movement towards, the enemy.

113. A fleet ranged thus might sail, with the wind, suppose at north, on any course from E.N.E. round by the south, and from thence haul up to W.N.W.; but

here the use of the sail ceases, and that of steam propulsion continues or may commence. Steam ships can manœuvre in any direction, in calms, and up to the wind's eye; and a well-constituted and skilfully-commanded steam fleet might, by acting in the space, or on courses where a sailing fleet cannot manœuvre, sink, burn, or capture the ships of such a fleet even of far superior force.

114. The order of retreat before the wind, on two lines of bearing, making with each other an angle of 135°, is represented in fig. 12, from which it may

Fig. 12.

W.N.W.

.135°

E.N.E.

be seen, by the lines of fire, how the ships defend each other towards the rear, reciprocally, and check the enemy's pursuit by the fires of their respective stern batteries; and likewise how strong this order is on both flanks by the crossing of the stern fires with both the broadside batteries of the ship at the angle, and with the outward broadsides fires of all the other ships in this order.

The invention of this order of retreat has been erroneously stated to be of very recent date; but the reader will find that it is fully described by Paul Hoste in his Treatise (p. 42, Captain Boswall's Translation), as that which was practised by Van Tromp in the naval combat off Portland in 1653. The retreat of Admiral Cornwallis, in 1796, was also conducted on this principle. (James, vol. i. p. 240.)

115. Paul Hoste, sensible that the order of sailing