Xenophon (Cyropaedia, 1. vii. [5 60] p. 540) has stated the specious reasons which engaged Cyrus to intrust his person to the guard of eunuchs. He had observed in animals, that, although the practice of castration might tame their ungovernable fierceness, it did not diminish their strength or spirit; and he persuaded himself that those who were separated from the rest of human kind would be more firmly attached to the person of their benefactor. But a long experience has contradicted the judgment of Cyrus. Some particular instances may occur of eunuchs distinguished by their fidelity, their valour, and their abilities; but if we examine the general history of Persia, India, and China, we shall find that the power of the eunuchs has uniformly marked the decline and fall of every dynasty.