78. In August 1874 the inhabitants of the towns situated on the north, west, and east sides of the mountain, were awakened by loud subterranean rumblings. Soon afterwards a formidable column of black smoke issued from the crater, accompanied by sand, scoriæ, and ignited matter (_infuocata materia_). Severe shocks of earthquake were felt, the centre of impulsion being apparently situated on the northern flank of the mountain, at a height of 2450 metres above the level of the sea. Some small _bocche eruttive_ opened near the great crater, and ejected lava, but the quantity was comparatively small, and but little damage was done. An account of this eruption was given by Silvestri in 1874, in a small pamphlet entitled, _Notizie sulla eruzione dell' Etna del 29 Agosto, 1874_. Since 1874 the mountain has been in a quiescent state. The centre of disturbance was at an elevation of 2450 metres (7600 feet) above the sea, on the north side of the crater, and between the minor cones known as the _Fratelli Pii_ and _Monte Grigio_. A new crater, having an elliptical contour, and a diameter of about 100 metres, was formed at this point. It is composed of a prehistoric grey labradorite, and of doleritic lava. Downwards from the main crater, in the direction of Monte di Mojo, a long fissure extended for 400 metres, and along the line of this fissure no less than _thirty-five_ minor cones opened, with craters of from thirty to three metres in diameter. The stream of lava ejected from the various _boccarelle_ was 400 metres long, 80 wide, and 2 metres in thickness, and the bulk of volcanic material brought to the surface, including the principal cone and its thirty-five subordinates and their ejectamenta, was calculated to amount to 1,351,000 cubic metres. The lava is of an augitic character, and magnetic; it possesses a specific gravity of 2·3636 at 25° C. It will be seen from the account of the foregoing eruptions that there is a great similarity in the character of the eruptions of Etna. Earthquakes presage the outburst; loud explosions follow, rifts and _bocche del fuoco_ open in the sides of the mountain; smoke, sand, ashes, and scoriæ are discharged, the action localises itself in one or more craters, cinders are thrown up, and accumulate around the crater and cone, ultimately lava rises, and frequently breaks down one side of the cone, where the resistance is least. Then the eruption is at an end.