Three line chalk box
作者： Romero Fred
DOI:
关键词: Geology 、 Geometry 、 Line (text file)
摘要:
lens.org 参考文章(5)
Robert K Landon, Chalk line box ,(1952)
Fred F. Prihoda, Multiple clothesline reel ,(1950)
Emil F Holinger, Computing tape-measure. ,(1907)
Jay M Darrow, Combination-tool for carpenters' use. ,(1907)
John E Giffin, Chalk-line holder. ,(1910)