A point of some importance in towing in a seaway is to keep the ships "in step as nearly as may be; that is, to use such a length of line that they shall meet the waves and ride over them together. If the length of the line is such that one vessel is in the trough of the sea as the other is on the crest, the line will for a moment slacken, then tauten out with a sudden jerk; whereas if they meet the waves at the same time the tension on the line will remain comparatively steady. The wavelengths of a sea are usually approximately uniform at any given time, and it should not be difficult to arrange the line as above described by heaving in or veering away the cable on the tow. In towing for a long time and covering a great distance, extreme variations may of course be found in wave-lengths, and the inconvenience of changing the length of the line from time to time may more than offset the advantage to be gained; but it is worth while to recognize this point and to be ready to take advantage of it when circumstances permit.

If the towing ship has a chock at the stern and amidships or nearly so, the line should be brought in through this. It is a good plan to use a short length of chain for the lead through the chock, shackling outside to an eye in the end of the wire-line, and inside to a pendant or span from the turret, the bitts, or elsewhere, according to the arrangement decided upon for securing. The chain through the chock not only takes the chafe-under which the wire would cut through-but by its flexibility does away with the dangerous "nip" which would be thrown into the wire if the tow chanced to take a rank sheer off onto the quarter.

If it is thought that the chain may suffer from chafe, a perfectly efficient sleeve may be made by wrapping it with a sheet of copper from % to 4-inch thick.

If chain is not to be used for taking the chafe in the chock, the tow-line must be very carefully protected by chafing-gear, which it is well to put on in the shape of a long and bulky "pudding." The stiffness of such a pudding reduces the sharpness of the nip which without it would be thrown upon the wire from time to time by the sheering of the ships.

The arrangements for securing the line inboard on the towing ship will vary widely with conditions.

In men-of-war, a pendant of wire or chain is sometimes taken around the after turret, as in Plates 172 and 173. The first of these plates shows the method used in the British Navy where one battleship tows another. Two lines are used here—a plan which has some advantages and a good many disadvantages. The

second plate shows what is considered to be upon the whole the best arrangement for heavy towing. A wire pendant may of course be used around the turret, instead of the chain here shown.

In a ship having no turret, the pendant may be taken around a deck-house, with a few turns around the bitts on each side, as in Plate 173.

Where the strain is not too heavy to be taken by the bitts, the arrangement will be that shown in Plate 174, the line being taken around as many sets of bitts as are available. To divide the strain here, it is advisable to take only one or two turns around the first bitts, thus leaving the line free to "render" slightly and so transfer a portion of the strain.

In all of the arrangements shown in the plates, pelican-hooks are used for letting go. In the case illustrated in Plate 172, the hook has the weight of the tow at all times.

In the other cases, the strain is taken momentarily on the hook, relieving the shackle and admitting of knocking out the shacklepin, after which the pelican-hook is slipped. This arrangement entails a little delay, which, however, need not exceed a few seconds, and the whole arrangement is more secure than that of Plate 172.

If it is not convenient to use an extra shackle for the pelicanhook, the hook may be used directly on the chain, as in Fig. 2, Plate 174.

If no pelican-hook is at hand, a strap may be used on the chain or wire, outside of the shackle, and a heavy purchase hooked to this and taken to the winch. For letting go, the strain is taken by the winch long enough to disconnect at the shackle, after which the strap is cut. (Fig. 3, Plate 174.)

There are some conditions under which it is convenient to use a span on the towing ship, the two parts being brought in through the quarter-chocks. Generally speaking, this makes it rather easier for the towing ship to steer and the advantage gained in this respect may become important in cases where a small ship is dealing with a heavy tow. Where the line leads from a chock directly over the rudder, it binds the stern so that it can only swing in obedience to the helm, bv dragging the tow with it. A large ship can take care of this situation by the power of her steering gear, assisted, if necessary, by the screws; but a small ship with a heavy tow and with the line leading through the

stern chock, if she steers at all will be very sluggish. Tugs which are specially fitted for towing have their bitts well forward of the rudder, allowing a chance for the stern to swing; the fittings abaft the bitts being such as to let the line sweep freely across from one quarter to the other.

Where a span is used it may be of chain, wire or manila, chain being probably the best. In this, as in other cases, arrangements must be made for letting go quickly if necessary.

Where chain is used for the span, two lengths of bower-cable are gotten aft, one on each side, and passed through the quarterchocks. The outer ends are then brought in over the rail and connected together by an anchor shackle, to which the end of the towing hawser or chain is also made fast (Plate 175). A bullrope is made fast to the shackle, for lowering the span over the stern after the lines have been secured and for heaving the span up to the rail if the line parts or if it is desired to let go.

The details of securing the lines inboard must of course depend upon circumstances, but it is important to distribute the strain over as many sets of bitts as possible.

A convenient plan is to bring the tow-line in through the quarter-pipe on one side and bend a hawser to it from the other quarter-pipe at such a point outside that the two parts shall form a span of convenient length. The lines may be made fast around the bitts and to the mast or a deck house in practically the same way as in the methods already described. This plan has the advantage that by letting go the second line we get rid of the span at once and have to deal only with the tow-line itself.

On board the tow, the hawser is usually bent to the bower-cable (Plates 175, 176), although there may of course be many conditions under which some other arrangement will be necessary. If the cable cannot be used, it is desirable to use at least a short length of chain to take the chafe in the chock in the same manner as already described for securing on the towing ship. If even this is impracticable, abundant chafing-gear must be used, and this should be examined several times a day and renewed as often as may be necessary.

Where the bower cable is used, the line is bent or shackled to it and the cable veered away to the desired length, after which the windlass brakes are set up and springs, to take the real strain of towing, are put on as in Plate 176. It is well to have a shackle