The Da Vinci Notebooks at sacred-texts.com
The shepherds in the Romagna at the foot of the Apennines make peculiar large cavities in the mountains in the form of a horn, and on one side they fasten a horn. This little horn becomes one and the same with the said cavity and thus they produce by blowing into it a very loud noise. 584
248:584 : As to the Romagna see also No. 1046.