Many sailors never encounter ice, except in a cold drink. Canadian mariners, on the other hand, contend with everything from towering icebergs to an entire ocean frozen for most of the year. These vessels were developed to combat the mighty forces of winter. The ice-choked Northumberland Strait always bedevilled Prince Edward Island's winter shipping. Storms occasionally -killed travellers who ventured across the Strait in iceboats - little more than rowboats equipped with runners. The Dominion ordered the "Northern Light", having agreed to provide year-round steamer service as a condition of Prince Edward Island's entering confederation. E. W. Sewell of Lévis, Quebec, built the ship from wood because people believed ice would easily puncture iron-plated hulls. The "Northern Light"'s rounded hull rode upward if squeezed by floes. In such circumstances, the crew tried to roll the ship free by pushing barrels of water across the deck. Lacking a sufficiently powerful engine, however, the ship failed as an icebreaker. The ice often trapped and damaged her, although she soldiered on from 1876 until replaced in 1888. The 1978 Ice Vessels stamps present an interesting contrast of vessels old and new combating their natural enemy, ice. From the ice- scrubbed sides of the "Labrador" to the round-hulled "Northern Light", belching smoke while trying to develop enough power to force her way through the pack, Tom Bjanason's designs are authentic. The set is enlivened by the colour typography, the cheerful colour of the "Chief Justice Robinson's" hull and the bright signal flags of the "St. Roch" on trials. The delicate black steel engraving is appropriate to both the rigging of the early vessels and the complex lattice mast, radar antennas and aerials of the modern "Labrador".