Henry III., Edward I., Edward II., who was dethroned and put to death.
Edward III., Richard II., who was dethroned.
Henry IV., Henry V., Henry VI.; the crown passed to the house of York.
Edward IV., Edward V., Richard III.; the crown claimed and won by Henry Tudor.
Henry VII., Henry VIII., Edward VI.; usurpation of Lady Jane Grey.
Mary I., Elizabeth; the crown passed to the house of Stuart.
James I., Charles I.; Revolution.
Charles II., James II.; invasion of William of Orange.
William of Orange and Mary II., Anne; arrival of the house of Brunswick.
George I., George II., George III., George IV., William IV., Victoria. The law has proved faulty in the last case; but certainly there was a crisis in the reign of George IV.
As I am on the subject of the English princes, I will add another singular coincidence, though it has nothing to do with the fatality of numbers.
It is that Saturday has been a day of ill omen to the later kings.
