TOPSAIL HALYARDS, SHEETS, AND TACKS.
The topsail halyards in vessels under 10 tons consist of a single rope rove through a sheave hole under the eyes of the topmast rigging.
Yachts of 10 tons and over have a block which hooks to a strop or sling on the yard, or, if the topsail be a jib-headed one, to the head cringle. The standing part of the halyard has a running eye, which is put over the topmast, and rests on the eyes of the rigging ; the halyard is rove through the block (which is to be hooked to the yard), and through the sheave hole at the topmast head. It is best to have a couple of thumb cleats on the yard where it has to be slung ; there is then no danger of the strop slipping, or of the yard being wrongly slung.
When the topsail yard is of great length, as in most yachts of 40 tons and upwards, an upper halyard is provided (called also sometimes a tripping line or trip halyard, because the rope is of use in tripping the yard in hoisting or lowering). This is simply a single rope bent to the upper part of the yard, and rove through a sheave hole in the pole, above the eyes of the topmast rigging. The upper halyards are mainly useful in hoisting and for lowering to get the yard peaked ; however, for very long yards, if bent sufficiently near the upper end, they may in a small degree help to keep the peak of the sail from sagging to leeward, or prevent the yard bending.
The topsail sheet is always a single * Manilla rope. It leads through a cheek block on the gaff end, then through a block shackled to an eye bolt under the jaws of the gaff. In most racing vessels nowadays a pendant is used for this block, as shown in the diagram (Plate I.). The pendant should go round the mast with a running eye. By this arrange ment the strain is taken off the jaws of the gaff and consequently off the main halyards. The hauling part of the rope is generally put round one of the winches on the mast to " sheet " the topsail. The topsail tack is usually a strong piece of Manilla with a thimble spliced in it, to which the tack tackle is hooked.
Jib-topsail halyards and main-topmast-staysail halyards are usually single ropes rove through a tail block on topmast head; but one or two large vessels have a lower block, with a spring hook, which is hooked to the head of the sail. In such cases, the standing part of the halyards is fitted on the topmast head with a running eye or bight.