Class-work: Page 11 #1

1. In 1786, Benjamin Franklin wrote a letter to an English friend describing some observations he had made. Here is part of the letter.

“In American I have often observ’d that on the roofs of our shingled houses, where moss is apt to grow in northern Exposures, if there be anything on the Roof painted with white Lead, there is constantly a streak on the shingles from such paint down to the Eaves, on which no moss will grow, but the wood remains constantly and free from it.”

Think of a question and a hypothesis for this observation.