Currents in the San Juan Islands and Gulf Islands of B.C. can run upwards of 8 knots and often run counter to what one might expect or what standard current tables reveal. The Current Atlas is a pictorial representation of current flow in this area, based on a special computer and physical study conducted in the early 1980s. Each page represent an individual hour of the day and shows current flows with the use of hundreds of arrows, allowing you to easily determine general current flow as well as areas of back-eddies. The Current Atlas is a perpetual one, so you only have to buy it once. Each year, then, you only need to purchase a "Washburne's Table", which enables you to quickly determine which page in the Current Atlas to use for any hour of the day.