How does an anchor hold the boat? First, locate a suitable area according to the weather and sea conditions. Then, throw the anchor connected with chain into the water. Make sure the anchor was implanted in the sand or sea bed. The ship will be firmly tied in position by the grip power when the anchor connect with the sea bed.

If an anchored boat needs to sail again, how to unlock it? When raising the anchor and chain, boat will moves toward to it by a reactive force. The anchor stock will be pull up when the boat  is close and keep in a line with the chain. Make the crown as a fulcrum and take out the anchor fluke from the sand by lever principle. Bring back anchor chain until the anchor is pulled out of the water.