It is narrated from Sayyidah Aishah (may Allah be pleased with her) that whenever a person complained of some ailment, or had an ulcer or a wound, the Prophet (peace and blessings be upon him) would gesture with his finger like this (and Abu Bakr, the narrator, placed his index finger on the ground and then raised it) and say: 'Bismillah, turbatu ardina, bi-riqati ba'dina, yushfa saqimuna bi-idhni rabbina' (In the name of Allah, the soil of our land, with the saliva of some of us, so that our sick one may be cured by the permission of our Lord). This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it!