Definition of algebraical:
- "The Literature of Ecstasy", Albert Mordell.
- "The Mystery of 31 New Inn", R. Austin Freeman.
In that superstitious age, when emperors and princes daily investigated the future, by alchemy, by astrology, and by books of fate, filled with formula; as gravely and precisely set forth as algebraical equations; when men of every class, from monarch to peasant, implicitly believed in supernatural portents and prophecies, it was not singular that a somewhat striking appearance, observed in the sky some weeks previously to the battle of Mookerheyde, should have inspired many persons with a shuddering sense of impending evil.- "The Rise of the Dutch Republic, Volume II.(of III) 1566-74", John Lothrop Motley Last Updated: January 25, 2009.