Antique Dahl Mfg. Co. Master Slide Rule 48\" Made New York City For Sale

Antique Dahl Manufacturing Company of New York Master Slide Rule has a beautiful patina of years of use. No chips or cracks in the wood.  Ruler freely slides from 8 inches to 48 inches.  

Due to the basic printing on this, I believe this to be an early version of this simplistic, ingenious tool.  Between the 1 and 2 inch is printed \"Master Slide Rule\". Between 4 and 5 inch is printed \"Dahl Mfg. Co. N.Y.C\" and between 6 and 7 inch marks is printed \"Patented.\"

American Carpenter and Builder, 1 Sep. 1911, pg. 104, noted that Dahl, with offices now at 1 East 42nd St., was manufacturing the folding ruler called the Dahl Master Slide Rule, \"Carpenters, builders, glaziers, shademen, plumbers, in fact any one in the building trades that ever has use for a folding rule, should be interested in the Dahl Master Slide Rule, made by the Dahl Mfg. Co., 1 East 42nd St., New York. This rule is illustrated herewith, right side up, ready for inside measurement. The arrow indicates the exact inside dimensions. As can be seen this rule is particularly desirable for measuring the inside dimensions of doors, window trim, etc. When closed, the rule measures 8 inches. ... The Dahl Mfg. Co. also manufactures a full line of white finish sheet metal cabinets and metal shelving. ...\"