And as a preliminary to other mystic procedures, in order to avert the Evil Eye, the Hindus wave around the patient’s face seven pebbles taken from a spot where three roads meet, seven leaves of the date-palm, and seven bunches of leaves of the _bor_ tree.[534] It may not be surprising that such mysterious rites, whose efficacy depends chiefly on the magical potency of certain odd numbers, should be popular among the natives of India, but it is noteworthy that these numbers are equally influential in Christian lands. A multiplication of examples might serve to emphasize this fact, but would occupy too much space. Charms and formulas are commonly thrice repeated, probably in reference to the Holy Trinity. Of all the numbers arithmeticall, The number three is heald for principall, As well in naturall philosophy, As supernaturall theologie.[535] The Bavarian peasant, in passing through a haunted place, considers himself amply fortified against evil if he takes the precaution to carry three things; namely, (1) a new knife which has never cut anything, marked on the blade with three crosses; (2) a loaf of bread baked on Epiphany Eve; (3) a black cat.[536] V. ODD NUMBERS IN FOLK-MEDICINE In a volume containing a great variety of ancient charms and magical cures, collected by Marcellus Empiricus, a Latin writer of the fourth century A. D., in which volume various remedial measures are described with great minuteness, the even numbers seldom appear. Thus, for the removal of a foreign substance from the eye, one should rub the affected organ with the five fingers of the hand of the same side, and repeat thrice a charm of words. Again, for the cure of a sty on the eyelid, take nine grains of barley and poke the sty with each one separately, meanwhile repeating a magic formula in Greek. Then throw away the nine and do the same with seven, throw away the seven and do the same with five, and so with three and one. The early Saxon physicians in England seem also to have had faith in the peculiar virtues of the number nine, as is evident from many of their prescriptions, of which the following prefix to a lengthy Latin charm is a fair specimen:— For flying venom and every venomous swelling, on a Friday churn butter which has been milked from a neat or hind all of one colour, and let it not be mingled with water. Sing over it nine times a litany and nine times the _Paternoster_, and nine times this incantation.[537] In an ancient English manuscript (Harleian Collection, No. 585), frequent examples are given of the employment of odd numbers in therapeutics. Thus, for dropsical affections, a beverage containing alexander, betony, and fennel is to be drunk daily for seven days. “To expel venom,” centaury is to be taken for fifteen days, and a potion prepared from the seed of cress is extolled for its curative qualities if taken faithfully during three days.[538]