1879 -] 
during the Last Ten Years. 465 
west side of the mountain divided itself into two branches, 
the larger of which was 875 yards in width, and it flowed 
to a distance of 1425 yards in the Fossa della Vetrana in 
three hours. It then descended inco the Fossa di Faraone, 
where it again divided into two streams, one of which ran 
over the lava of 1868 in the Piano delle Novelle, while the 
other flowed through the Fossa di Faraglione over the lava 
of 1855, and reached the villages of Massa and S. Sebas- 
tiano. The stream passed between them, and afterwards 
continued its course through an artificially constructed 
channel, until it reached some highly cultivated ground, 
which it overwhelmed. The lava moved with great rapidity ; 
between 10 and 11 a.m. it traversed more than 3 miles, and 
covered an area of 2 square miles. The supply of lava fortu- 
nately ceased at this source, otherwise in less than twenty- 
four hours the stream would have reached Naples and 
flowed into the sea. About one-third of Massa was destroyed, 
and less than one-fourth of S. Sebastiano. The stream 
which separates the two villages is more than half a mile 
in breadth and 20 feet in depth. 
On the night of April 26th, 1872, the Vesuvius Observa- 
tory lay between two streams of lava, and the inmates found 
the radiated heat very oppressive. The lava seemed to 
ooze through the sides of the cone. The two craters which 
had opened near the edge of the great crater gave vent to 
loud bellowings, produced great clouds of smoke and ashes, 
and projected volcanic bombs to a height which Palmieri 
estimated at nearly 1500 feet. This would imply an initial 
velocity of 655 feet per second. The white ashes were 
carried by the wind as far as Cosenza. Dark-coloured 
sand, lapilli, fragments of scoriae, and much smoke were 
at intervals emitted during the eruption. Many people 
fled in terror from Naples ; Palmieri remained, however, at 
his post in the Observatory. 
On the morning of April 27th the lava ceased to flow. 
It was noticed that in three several places in the lava bed 
great masses of smoke were emitted, and projectiles were 
driven into the air, as if small volcanic rents were existing 
beneath. But this effeCt, which sometimes lasted from 
fifteen to twenty minutes, was probably due to the sudden 
evolution of gases produced by the passage of the lava over 
wet places. On the evening of the 27th the pine-tree cloud 
of smoke from the crater became darker in colour, and fre- 
quent flashes of lightning were emitted. On the following 
day the pile of ashes and lapilli was so great that it darkened 
the air, and great terror pervaded the inhabitants of Resina, 
