The elements of divination from the flight of birds were derived either from the significant notes and sounds of their voices, or from the manner in which their wings were flapped or their flight conducted. If the bird flew from the left to the right of the augur, it was considered a happy omen; if the flight was in the opposite direction, the enterprise in hand had to be abandoned or at least delayed. Augury by flight was usually applied to eagles and vultures, while woodpeckers, ravens, crows, and screech owls announced the will of the gods by note. The direction from which the note came, usually determined the nature of the augury. But, in the case of the screech owl, the sounds were always of evil omen, from whatever side they came. And those who have been so unfortunate as to hear its mournful, desolate and God-forsaken tones will not be disposed to censure either the Romans or their gods for the low esteem in which they held this bird. Again, it was a principle of Roman augury that auspices could be neutralized or overcome. If a crow furnished an omen, and an eagle gave another which was opposed to it, the first sign was wiped out, because the eagle was a larger and nobler bird than the crow. And, as in the case of prayer, so also in the matter of the auspices, a disturbing sound would destroy the effect of the augury. The squeak or cry of a mouse would destroy a message from Jupiter conveyed in the scream of an eagle. But the most potent manifestation of the divine mind, among the ancient Romans, was that derived from thunder and lightning. Lightning to them was the sovereign expression of the will of the gods; and a single flash blotted out every other sign and token. It was an irrevocable presage and could not be remotely modified or evaded. It came directly from the hand of the deity and was an emphatic revelation of the divine mind. All places struck by lightning were considered sacred and were consecrated to the god who had sent the bolt. Upon the spot where it fell, an altar was raised and an inclosure formed. The service of consecration consisted in burying the lightning, that is, in restoring the earth thrown up by it, and in the sacrifice of a two-year-old sheep. All such places were considered hallowed spots and it was impious and sacrilegious to touch them or even look at them. The gods deprived of reason those who destroyed the altars and sacred inclosures of these places. These various methods of ascertaining the will of the deities were employed in every important transaction of Roman public and private life. At times, all of them coöperated on occasions of vast import and when the lives and destinies of great men were involved. The following single paragraph from Suetonius contains allusions to all the modes of divination which we have just discussed: