Messenger of Allah ﷺ performed Tawaf (of the Kaʿba) riding a camel (at that time the Prophet ﷺ had a foot injury). Whenever he came to the Corner (having the Black Stone) he would point out towards it with a thing in his hand and say, "Allahu-Akbar." (Using translation from Bukhārī 1632)  

«أَنَّ رَسُولَ اللَّهِ ﷺ طَافَ بِالْبَيْتِ عَلَى بَعِيرٍ كُلَّمَا أَتَى عَلَى الرُّكْنِ أَشَارَ إِلَيْهِ بِشَيْءٍ فِي يَدِهِ وَكَبَّرَ»