The Search after Let us reflect further that those who have more fire or a little wine in their heads are swifter than others; that among animals, those who have more agitated spirits, such as birds, move more swiftly than those with cold blood such as frogs, and that there are even some, such as the chameleon, the tortoise, and some insects, whose spirits are agitated so little that their muscles are not filled any more swiftly than a small balloon into which one would blow.