Galen’s own works are not entirely free from the magical devices of which he accuses others. We may begin with animal substances, since he himself has testified that the use of sweat, crocodile’s blood, and mouse’s dung is suggestive of magic. Moreover, he attributes more bizarre virtues to the parts of animals than to herbs or stones. In a passage somewhat similar to that in which Pliny[763] expressed his horror at the use of human blood, entrails, and skulls as medicines, Galen declares that he will not mention the abominable and detestable, as Xenocrates and some others have done. The Roman law has long forbidden eating human flesh, while Galen regards even the mention of certain secretions and excrements of the human body as offensive to modest ears.[764] Nevertheless, before long he offends against his own standard and describes how he administered to patients the very substance which he had before characterized as most unmentionable.[765] It may also be noted that he repeats unquestioningly such a tale as that the cubs of the bear are born unformed and licked into shape by their mother.[766] [Sidenote: Nastiness of ancient medicine.] Further milder illustrations of the fact that such nasty substances were then not merely recommended in books but freely employed in actual medical practice, are seen in the frequent use by one of Galen’s teachers of the dung of dogs who for two days before had eaten nothing but bones,[767] in Galen’s own wonderfully successful treatment of a tumor on a rustic’s knee with goat dung—which is, however, too sharp for the skins of children or city ladies,[768] and in his discovery by repeated experience that the dung of doves who take little exercise is less potent than that of those who take much,[769] Galen also says that he has known of doctors who have cured many persons by giving them burnt human bones in drink without their knowledge.[770] [Sidenote: Parts of animals.]