Excellent picture of the canal docked sailing vessel across from the Saxon style house. The depth of the canal is measured by the depth distance from the keel to bottom or if of design, from centre vertical keel board to bottom.
For harbour sailing as kids, were to use a praam built with an uplifted blunt bow to clear the waves and if close to the mouth entrance to clear the swells. If the sea was calm then it was safe to go out a few km from shore for a tast of good winds. The max lean under sail for most sail power was about 30 degrees before loss of stability. Yes, more then once were to exceed the lean to dip the sail and capsize. It to do this, it takes a great deal to stow the sail, right the flooded boat to then begin the task of bailing out a ton of water to once again float. But, it was harmless fun and a great teacher of handling emergencies such as a capsize at sea.