A WELCOME ADDITION to the growing number of Canadian military historical studies is Tin-Pots and Pirate Ships: Canadian Naval Forces and German Raiders 1880-1918 (McGill-Queen`s, 391 pages, $34.95 cloth). The authors, Michael L. Hadley and Roger Sarty, chart the origins of our navy from the late 19th century to the point at the end of the First World War when we had almost 200 vessels. Those boats, known as the "Bum Boat Fleet;" were a motley collection of ships, fisheries cruisers, and even private yachts whose crews were to a large extent unfamiliar with the ways of the sea. Canada`s need for a navy, on the other hand, was evident. As far back as the 1880s Germany had developed plans to attack North America, and by the time the war broke out it had created the U-boat, a weapon that utterly transformed naval warfare. Much of Hadley and Sarty`s superbly presented material focuses on that menace, as well as British reluctance to send much help to Canadian waters - both of which inspired what little navy we had during the First World War. In 1918, when U-boat operations were in full force, dozens of allied ships were attacked and sunk off the east coast of the United States and the Maritimes. The Canadian whose job it was to contend with the threat was Captain Walter Hose, who commanded the antisubmarine flotilla in 1917-18. He tried hard, but had little to work with. Ironically, after the war, Canada had even less of a navy it was virtually dismantled. Canadians would not stand for large military expenditure and, unlike the Germans, had no visions of imperial grandeur and no humiliating wounds to lick. Some studies already exist on the subject, but perhaps Hadley and Sarty will provide us with their own sequel about Canada`s improvised navy and its scramble toward the next war.