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324 place of falling on the pavement, 40 or 50 feet from where they stood, they would have flown through the air, a mile or two, and so of every other body.

This point would scarcely seem to need prolonged remark, were it not that up to this time, it appears to have been almost universally misconceived; even Humboldt appears never to have formed in his mind any clear conception of the distinction, and Nöggerath and Schmidt, in their excellent accounts of the Rhenish and Hungarian shocks, have apparently equally lost sight of it, as they busy themselves exdusively, with ascertaining exactly, the velocity of transit, and make even no allusion, to the proper velocity of the wave, which, for all purposes of seismodynamics, is the far more important element to determine.

Over the whole wide area of commotion examined, it has been seen, (Part II.) that I was able to obtain only six reliable records of the precise moment of the arrival of the shock, at the same number of localities, viz., at Naples, Vietri di Potenza, Monte Peloso, (D'Errico's station,) Atella, Barielle, and Melfi. These six, however, afford tolerably accordant results, far more so than could have been expected from observations made in a country so backward as to knowledge, and where the accurate public measurement of time—one of the surest indications of advancing civilization—is absolutely unknown. The recorded times, and their reduction to Naples mean time, respectively, are given, for each of the above stations, in their proper places (Part II.). It is only necessary here, therefore, to compare them, with the distances from the seismic vertical, in order to obtain the transit velocities.

Melfi, Vietri di Potenza, and the seismic vertical, close