Comment on " Inferring the depth of preinstrumental earthquakes from macroseismic intensity data: a case-history from Northern Italy". Natureresearch, Scientific Reports, 1-13 (2019). Sbarra, P., Burrato, P., Tosi, P., Vannoli, P., De Rubeis, V. & Valensise

We have read with interest the article in question[1], because it proposes a technique for inferring the depth of pre-instrumental earthquakes. Our interest was increased by two circumstances: i) the authors announce that they have even developed the Rosetta Stone to obtain the hypocentral depth of earthquakes from their macroseismic intensities and then to re-determine their magnitudes; ii) we hoped that these results could be useful to improve the KF-NGA source inversion procedure[2]-[7]. In fact, unfortunately, the main weakness of KF-NGA is the determination of the hypocentral depth (mostly because KF-NGA does not include a propagation model of the Crust).