Viewegs Geschichte der Chemie

That all plants depend directly and substantially on the element of water, I learned from the following experiment: I took an earthen vessel and poured into it two hundred pounds of earth which I had previously dried in an oven. I watered it with rainwater and planted a willow tree that weighed five pounds. Five years later it had grown into a tree that weighed one hundred and sixty-nine pounds and about three ounces. Only rain (or distilled water) was added. The large container was set in soil and covered at the top with a galvanized iron plate in which were many k1eine holes. I did not weigh the weight of the leaves that fell during the four autumn seasons. Finally, I dried the soil in the jar again and Pds. and in about the same two hundred pounds ago, though two ounces less. So one hundred and four ounces developed.