Position or direction is often an important matter in Pliny’s, as in magic, ceremonial. It perhaps comes out most frequently in his specification of right or left. An aching tooth should be scarified with the left eye-tooth of a dog; a spider which is placed with oil in the ear should be caught with the left hand;[412] epilepsy may be cured if a virgin touches the sufferer with her right thumb;[413] for ophthalmia of the right eye suspend the right eye of a frog from the patient’s neck, and the left eye for the left eye;[414] for lumbago tear off an eagle’s feet away from the joint, and use the right foot for the right side and the left for pain in the left side.[415] But we have met other examples already, and also cases of the use of the upper or lower part of this or that according to the corresponding location of an aching tooth in the upper or lower jaw.[416] Tracing circles with and about objects, facing towards this or that point of the compass, the prohibition against glancing behind one, and the stress laid upon finding things or killing animals between the ruts of cart wheels, are other examples of taking into consideration position and direction which we have already met with incidentally to the treatment of other topics. The prescription of a plant which has grown on the head of a statue and of another which has taken root in a sieve thrown into a hedge[417] also seem to take mere position largely into account, more so than the accompanying recommendation of an herb growing on the banks of a stream and of another growing upon a dunghill.[418] [Sidenote: The time element.] The element of time is also important. Operations should be performed before sunrise, early in the morning, at night, and so on. The moon is especially regarded in such directions.[419] When we are informed that sufferers from quartan fever should be rubbed all over with the fat of a tortoise, we are also told that the tortoise will be fattest on the fifteenth day of the moon and that the patient should be anointed on the sixteenth.[420] But this waxing and waning of the tortoise with the moon is primarily a matter of astrology and planetary influence, under which heading we shall also later speak of Pliny’s observance of the rising of the dog-star. [Sidenote: Observance of number.]