Reconstruction, one of the most turbulent and controversial eras in American history, began during the Civil War and ended in 1877. It witnessed America's first experiment in interracial democracy.
1 Changes in skin color. 2  A chemical peel can cause treated skin to become darker than normal (hyperpigmentation) or lighter than normal (hypopigmentation). 3  Hyperpigmentation is more common after superficial peels, while hypopigmentation is more common after a deep peel.
Once these chemicals are applied, they turn greasy and black. The only way to get it, and the algae off your roof, is with a good deal of pressure using a pressure washer. A garden hose will not work. Store bought roof cleaning chemicals or do it yourself roof cleaners are nothing more than gimmicks that do not work.