Climacteric

By the climacteric system, seven years was declared to be the termination of childhood; fourteen the term of puberty; twenty-one of adult age; thirty-five, or five times seven, as the height of physical and bodily strength. At forty-nine the person was said to have reached the height of his mental strength or intellectual powers; at sixty-three, or nine times seven, he was said to have reached the grand climacteric.

- T. Ellwood Zell's Popular Encyclopedia of knowledge and Language, 1871