Observance of number is another feature in Pliny’s ceremonial, of which we have already met instances. He also alludes to the writings of Pythagoras on the subject and ascribes to Democritus a work on the number four. Pliny’s recipes frequently recommend that the operation be thrice repeated. In the case of curing scrofula by the ashes of vipers he prescribes three fingers thereof taken in drink for thrice seven days.[421] In another application of a Gallic herb with old axle-grease which has not touched iron, not only must the patient spit thrice to the right, but the remedy is more efficacious if three men representing three different nations anoint the right side with it.[422] The virtue of the number one is not, however, entirely slighted. Importance is attached to the death of a stag from a single wound.[423] Sometimes three and one are joined in the same operation, as when child-birth is aided by hurling through the house a stone or weapon by which three animals, a man, a boar, and a bear, have been killed with single blows. One of the discoveries of Pythagoras which seldom fails is that an odd number of vowels in a child’s given name portends lameness, blindness, and like incapacitation on the right side of its body, and an even number, injuries on the left side.[424] In a crown of smilax for headache there should be an odd number of leaves,[425] and in a diet of snails prescribed for stomach trouble an odd number are to be eaten.[426] For a head-wash ten green lizards are boiled in ten _sextarii_ of oil,[427] and for an application to prevent eyelashes from growing again when they have been pulled out fifteen frogs are impaled on fifteen bulrushes.[428] The person who has tied on a certain amulet is thereafter excluded from the patient’s sight for five days.[429] And so on. [Sidenote: Relation between operator and patient.] This last item suggests a further intangible factor in Pliny’s procedure, the doing of things to or for the patient without his knowledge. But this and any other incorporeal relationships existing between operator and patient should perhaps be classed under the head of sympathy and antipathy. [Sidenote: Incantations.]