File:JapanHomes030 THE SUMI-TSUBO.jpg

English: From the original book: "The sumi-tsubo (fig. 30, A, B) is the substitute for our carpenter's chalk-line; it is made of wood, often curiously wrought, having at one end a cavity scooped out and filled with cotton saturated with ink, and the other end has a reel with a little crank. Upon the reel is wound a long cord, the free end of which passes through the cotton, and out through a hole at the end of the instrument. To the end of the cord is secured an object resembling an awl. To make a line on a plank or board the awl is driven into the wood, the cord is unreeled, and in this act it becomes blackened with ink; by snapping the cord in the usual way, a clear black line is left upon the surface of the wood. II is then quickly reeled up again by means of a little crank. This instrument is an improvement in every way over the chalk-line, as it is more convenient, and by its use a clear black line is left upon the wood, instead of the dim chalk-line which is so easily effaced. This implement is often used as a plumb-line by giving a turn to the cord about the handle, thus holding it firmly, and suspend the instrument by means of the awl....The sumi-tsubo was much more simple and primitive in form in those times [" five hundred and seventy years ago"], judging from the sketch given on page 42 (fig. 30, C)."