Zon, Raphael, 1874-1956, Graves, Henry Solon, 1871-1951 · Washington, D.C. : U.S. Dept. of Agriculture, Forest Service · leaf 44
ormal shade. METHODS OF DETERMINING TOLERANCE. 39 made at a time. The photometer is made of aluminum; it weighsbut a few ounces and may be conveniently carried in the pocket. The sensitive paper is a commercial printing paper sold on themarket as solio. The photographic paper, the most…
Plants Effect of light on · Trees Growth · Light Effect on trees · Tree growth
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer03inte-694-400.webp)
