logs can be sawn into boards or planks in two basic ways, either by cutting straight through from one side to the other, known as plain or flat sawn, or to cut in a radial direction where the rings meet the board at an angle of more than 45 degrees. Plain sawn timber is more prone to cupping and is less durable when used as flooring. The circular saw was invented in 1777.Pit saws where the log was positioned over a pit with a man above (lifting) and one below (guiding) was the traditional method of sawing timber along its length. The man below got filthy, and while the man above worked harder he was "top dog" - the origin of the expression. While on the subject of sayings, timber was first sawn on trestles, the log was balanced at its centre, one end was raised and sawn, and then the process was repeated to the other end, hence - "see saw".