When this jigger was abolished the sail retained its lateen shape, got on to the mainmast, and became what we may call a main crossjack, thereby rendering a square mainsail impossible.
When the crossjack was replaced by a gaff, the larger vessels started the square mainsail, and became "brigs," while the smaller kept the spanker as their mainsail, and became "brigantines," so that a genuine old brigantine is a brig without a square mainsail.
Soon, however, vessels appeared with no yards at all on their mainmasts, and these were called "hermaphrodite brigs," and were found to be so handy that they crowded the old brigantines off the sea and took their name.
But here a qualification must come in. Perhaps you have seen a two-masted vessel with yards on her foremast and none on her main. She is a "topsail-schooner." In what does she differ from the brigantine? The brigantine has a foremast of three spars from the old snow, and a mainmast of two from the hermaphrodite; the topsail-schooner has both foremast and mainmast of two spars, and the foresail on a gaff instead of on a yard, and in other ways is different, but a glance at the foremast is enough to distinguish her from a brigantine.
A "three-masted schooner" has only lower masts and topmasts, and each mast is rigged for fore-and-aft sails, but more often than not these vessels carry yards at the fore and sometimes at the main.
With the "ketch" begins what has been called the mast-and-a-half division of sailing vessels. The tall mast is the mainmast, the short mast is the mizzen; some ketches carry square sails on the main, some carry a topsail on the mizzen—the distinctive mark of the ketch being that the mizzen is a pole-mast and stepped in front of the stern-post. If the mizzen be stepped abaft the stern-post the vessel becomes a "dandy" or "yawl."
In the cutter the mizzen is dispensed with, and in a sloop of the old rig the difference between the two is that the cutter has two headsails, the jib and foresail, while the sloop has but one, the foresail.
Sometimes the sloop has a standing bowsprit, while the cutter has a running one; but this distinction is not essential. Indeed, the words cutter and sloop have begun to be used indiscriminately, except, perhaps, that a cutter is for pleasure and a sloop for trade.
In a spritsail rig the gaff is at the head of the sail, and works on the mast in cheeks; the sprit runs diagonally across the sail, and is hung on to the mast in what is practically a loop and lashing.
This has also what looks like a mizzen, but it is fixed on to the rudder and is known as a "jigger." Sometimes the jigger is triangular, like the yawl's mizzen, but the shape makes no difference in the name.