Benjamin Franklin learned that plaster sown in the fields would make things grow. He told his neighbors, but they did not believe him and they argued with him trying to prove that plaster could be of no use at all to grass or grain.
After a little while he allowed the matter to drop and said no more about it. But he went into the field early the next spring and sowed some grain. Close by the path, where men would walk, he traced some letters with his finger and put plaster into them and then sowed his seed in the field.
After a week or two the seed sprang up. His neighbors, as they passed that way, were very much surprised to see, in brighter green than all the rest of the field, the writing in large letters, "This has been plastered." Benjamin Franklin did not need to
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