Small two-masted vessels with square sails and a bowsprit were called snows. In the 17th -18th centuries they were widely spread in England, France and Sweden. A snow carried two masts with square sails, a bowsprit, a staysail and a jib. The sails and rigging on the fore- and the mainmasts were placed in the same manner as in three-masted ships. The main peculiarity of a snow was a snow- or a trysailmast. It was a thin mast installed on the deck in a wooden block just behind the mainmast. The top was fastened by an iron stirrup or a crossed wooden beam on (or under) the back side of the main top. Usually fighting snows were called corvettes or sloop-of-wars. Often they did not carry a snow-mast and at its placement a rope was laid - "jack-stay", which was lashed on dead-eyes. The mizzenmast was strengthened to this stay and the gaff at that was unhoisted. The length of a snow was 20 - 30 m, the width - 5 - 7.5 m, displacement - nearly 150 t, her crew reached up to 80 people. Fighting snows were armed by 12 - 18 guns of a smaller caliber and snows were used for reconnaissance and message services.