One book error is prevalent in our country which should be corrected. It is predicated upon hereditary notions of blood, and is anti-republican. Some of our latest writers promulgate the idea that the criminal conduct of _one_ member of a family disgraces the _whole_. In a community purely republican, every individual is judged according to his or her own deeds, and no act in one can criminate or disgrace another who is innocent. The very writers amongst us who thoughtlessly publish this _imported_ sentiment, pursue a different course practically, and treat others agreeably to their merit, without reference to the conduct of their relations. Their practice is better than their theory. But few families in America can trace their ancestors as far back as the Rodneys of Delaware. This name was introduced into England with the Norman queen Maud or Matilda, as early as 1141, and stands among the foremost on the list of military fame acquired during the Norman conquest and at subsequent periods. To those who are conversant with the history of the stormy times of that kingdom, the name of Sir Walter De Rodeney, and others of the same line, is familiar. They were able in council and in war, they figured in the civil, military and naval departments, and received the highest honours that could be awarded to their rank by kings and queens. They were also remarkable for magnanimity and liberality. Under the auspices of William Penn, a branch of this ancient family, William Rodney, came to Philadelphia and finally settled in Kent, Delaware. He was the son of William Rodney, of England, who married Miss Alice, daughter of Sir Thomas Cæsar, a wealthy merchant. William Rodney, who located at Kent, left one son, Cæsar, who was the father of the subject of this sketch. CÆSAR RODNEY was a native of Dover, Kent county, Delaware, and born in 1730. He appears to have received a good education, and at the death of his father inherited an ample fortune in real estate. He was a slender man physically, with an animated countenance, easy and pleasing in his manners and gentlemanly in his intercourse. Owing to a cancer upon his nose, which commenced its ravages upon him at an early age, he became greatly emaciated, and long before his death was emphatically a moving skeleton. The cancer having spread over one side of his face, he was compelled for many years to wear a silk bandage over it. Notwithstanding this affliction he was uniformly sprightly and cheerful. With a strong and penetrating mind, firmness of purpose and decision of character, he united an abundant share of keen wit and good humour, that rendered him an agreeable companion—his vast stock of experimental intelligence and practical knowledge rendered him an instructive one.