Other stones guard treasuries by sounding a trumpet-like alarm at the approach of thieves; or change color four times a day and are ordinarily visible only to young girls. But if a virgin of marriageable age chances to see this stone, she is safe from attempts upon her chastity henceforth.[980] Some stones drive men mad and are connected with the Mother of the Gods or are found only during the celebration of the mysteries.[981] Others stop dogs from barking, expel demons, grow black in the hands of false witnesses, protect from wild beasts, and have varied medicinal powers or other effects similar to those already mentioned in the case of herbs.[982] In a river where the Spartans were defeated is a stone which leaps towards the bank, if it hears a trumpet, but sinks at the mention of the Athenians.[983] Certainly a marvelous stone, capable of both hearing and motion! [Sidenote: Fascination.] Leaving the treatise on rivers and mountains, for the occult virtue of human beings we may turn to a discussion of fascination in the _Symposiacs_.[984] Some of the company ridiculed the idea, but their host asserted that a myriad of events went to prove it and that if you reject a thing simply because you cannot give a reason for it, you “take away the marvelous from all things.” He pointed out that some men hurt little and tender children by looking at them, and argued that, as the plumes of other birds are ruined when mixed with those of the eagle, so men may injure by their touch or mere glance. Plutarch, who was of the company, suggested effluvia or emanations from the body as a possible explanation, pointing out that love begins with glances, that no disease is more contagious than sore eyes, and that gazing upon the curlew cures jaundice. The bird appears to attract the disease to itself, and averts its head and closes its eyes, not, as some think, because it is jealous of the remedy sought from it, but because it feels wounded as if from a blow. Others of the company contended that the passions and affections of the soul may have a powerful effect through the eyes and glance upon other persons, and argued that the sufferings of the soul strengthen the powers of the body, and that the same counter-charms are efficacious against envy as against fascination. The emanations which Democritus believed that envious and malicious persons sent forth are also mentioned; fathers have fascinated their own children, and it is even possible that one might injure oneself by reflection of one’s gaze. It is suggested that young children may sometimes be fascinated in this manner rather than by the glance of others. [Sidenote: Animal sagacity and remedies.]