AUGUST 21, 1902] 
Both volcanoes are of the same type, simple cones with a 
large vent near the summit and without parasitic craters. 
They are both deeply scored with ravines, and on their south - 
west sides there is a broad valley—occupied at Martinique by 
St. Pierre City, at St. Vincent by the Wallibu. It is in these 
valleys that the destruction has been most pronounced. In 
both, the recent eruptions have been characterised by paroxysmal 
discharges of incandescent ashes, and a complete absence of 
lava streams. 
In St. Vincent, however, the mass of material ejected has 
been much greater, and a considerably larger area of country 
has been devastated than in Martinique. That the loss of life 
was not so large can be accounted for by the absence of a populous 
city at the foot of the mountain. Had the city of St. Pierre 
been planted at the mouth of the Wallibu, there can be no doubt 
it would have been equally completely destroyed. 
On Mont Pelée, we understand that a fissure has opened on 
the south side of the mountain between the summit and 
St. Pierre, from which the blast was emitted which over- 
whelmed the city. But on the Soufriére the old orifices have 
been made use of. The eruption of Pelée began with the flow 
of mud lavas, but none such were seen in St. Vincent. On the 
other hand, the hot blast which swept down on the doomed 
city was essentially similar to that which we have described as 
having taken place at the Soufriére. Both eruptions produced 
principally hot sand and dust, with a small proportion of bombs 
and ejected blocks. 
Observations of an Eruption of Mont Pelee. 
We were fortunate in having an opportunity to witness one of 
the more important eruptions of Mont Pelée before we left 
Martinique, and this enabled us to see how far the actual pheno- 
mena corresponded with the ideas we had been led to form from 
an inspection of the effects of the earlier outbursts. On July 9 we 
were in a small sloop of 10 tons, the A/inmerva, of Grenada, 
which we had hired to act as a convenient base for our expedi- 
tions on the mountain. The morning was spent in St. Pierre 
City, and on the sugar-cane plantations on the lower slopes of 
the mountain on the banks of the Riviere des Peres. The 
volcano was beautifully clear. Every ravine and furrow, every 
ridge and crag, on its gaunt naked surface stood out clearly in 
the sunlight. Thin clouds veiled the summit, but now and then 
the mist would lift sufficiently to show us the jagged broken cliff 
which overlooks the cleft. From the triangular fissure which 
serves as the crater hardly a whiff of steam was seen to rise, and 
the great heap of hot boulders which lies on the north side of 
and above this fissure could be perfectly made out. Swall 
land-slides took place in it occasionally, and small jets of steam 
rose now and again from between the stones. 
A little after mid-day large steam clouds began to rise, one 
every 10 or 20 minutes, with a lowrumble. As they rose they 
expanded, becoming club-shaped and consisting of many globular 
rolling masses, constantly increasing in number and in size as 
they ascended in the air. They might be compared to a bunch 
of grapes, large and small, or to a gigantic cauliflower. When 
their upward velocity diminished they floated away to leeward, 
and fine ash rained down in a dense mist as they drifted over 
the western side of the mountain. They occasioned no anxiety 
in our minds, as we had found that the mountain was never long 
without exhibiting these discharges, and they were due merely 
to an escape of steam carrying with it fine dust. They rose, as 
a rule, to heights of 5000 or 6000 feet above the sea. 
That afternoon as the sun was getting lower in the heavens 
and the details of ravine and spur showed a contrast of light 
and shadow which was absent at mid-day, we sailed along from 
St. Pierre to Précheur, intention obtaining a series of general 
photographs of the hill. The steam puffs continued, and, about 
6 o’clock, as we were standing back across the bay of St. 
Pierre, they became more numerous, though not much larger in 
size. We ran down to Carbet, a village 14 miles south of St. 
Pierre, where there is a supply of excellent water and good 
anchorage. About half-past six it was obvious that the activity 
of the mountain was increasing. The cauliflower clouds were 
no longer distinct and separate, each following the other after an 
interval, but arose in such rapid succession that they were 
blended in a continuous emission. A thick cloud of steam 
streamed away before the wind so laden with dust that all the 
leeward side of the hill, and the sea for 6 miles from the shore, 
was covered with a dense pall of fine falling ash. The sun 
setting behind this cloud lost all its brightness, and became a 
NO. 1712, VOL. 66] 
NATURE 
405 
pale yellowish-green disc, easily observable with the naked eye. 
Darkness followed the short twilight of the tropics, but a 4 days’ 
old moon shed sufficient light to enable us to see what was 
happening on the hill-side. ; 
An Incandescent Avalanche. 
Just before darkness closed in, we noticed a cloud which had 
in it something peculiar, hanging over the lip of the fissure. At 
first glance it resembled the globular cauliflower masses of steam. 
It was, however, darker in colour, and did not ascend in the air 
or float away, but retained its shape, and slowly got larger and 
larger. After observing it for a short time, we concluded that 
it was travelling straight down the hill towards us, expanding 
somewhat as it came, but not rising in the air, only rolling over 
the surface of the ground. It was so totally distinct in its 
behaviour from the ascending steam clouds that our attention 
was riveted on it, and we were not without apprehension as to 
its character. It seemed to take some time to reach the sea 
(several minutes at least), and as it rolled over the bay we could, 
see that through it there played innumerable lightnings. We- 
weighed anchor and hoisted the sails, and in a few minutes 
were slipping southward along the coast with a slight easterly 
wind and a favourable tide. We had, however, scarcely got 
under way when it became clear that an eruption was impending. 
As the darkness deepened, a dull red reflection was seen in the 
trade-wind cloud which covered the mountain summit. This 
became brighter and brighter, and soon we saw red-hot stones 
projected from the crater, bowling down the mountain slopes, 
and giving off glowing sparks. Suddenly the whole cloud was 
brightly illuminated, and the sailors cried, ‘‘the mountain 
bursts!” In an incredibly short space of time a red-hot 
avalanche swept down to the sea. We could not see it start 
from the crater owing to the intervening veil of cloud, but the 
lower parts of the mountain were clear, and the glowing 
cataract poured over them right down to the shores of the bay. 
It was dull red, with a billowy surface, reminding one of a snow 
avalanche. In it there were larger stones which stood out as 
streaks of bright red, tumbling down and emitting showers of 
sparks. In a few seconds it was over. A loud angry growl 
had burst from the mountain at the moment when this avalanche 
was launched from the crater. It is difficult to say how long an 
interval elapsed between the time when the great glare burst on 
the summit and the incandescent avalanche reached the sea. 
Possibly it occupied a couple of minutes: it could hardly have 
been more. Undoubtedly the velocity was terrific. Had any 
buildings stood in its path they would have been utterly wiped, 
out, and no living creature could have surviyed that blast, 
The Lightning Discharges. 
Hardly had its red light faded when a rounded black cloud 
began to shape itself against the starlit sky, exactly where the 
avalanche had been. The pale moonlight shining on it showed 
us that it was globular, with a bulging surface, covered with 
rounded protuberant masses, which swelled and multiplied with 
a terrible energy. It rushed forward over the waters, directly 
towards us, boiling, and changing its form every instant. In 
its face there sparkled innumerable lightnings, short, and many 
of them horizontal. Especially at its base there was a con- 
tinuous scintillation. The cloud itself was black as night, 
dense and solid, and the flickering lightnings gave it an in- 
describably venomous appearance. It moved with great velocity, 
and as it approached it got larger and larger, but retained its 
rounded form. It did not spread out laterally, neither did it 
rise into the air, but swept on over the sea in surging globular 
masses, coruscating with lightnings. When about a mile from. 
us it was perceptibly slowing down. We then estimated that 
it was 2 miles broad and about 1 mile high. It began to 
change its form ; fresh protuberances ceased to shoot out or 
grew but slowly. They were less globular, and the face of the 
cloud more nearly resembled a black curtain draped in folds. 
At the same time it became paler and more grey in colour, and 
for a time the surface shimmered in the moonlight like a piece 
of silk. The particles of ash were now settling down, and the 
white steam, freed from entangled dust, was beginning to rise 
in the air. 
The cloud still travelled forward, but now was mostly steam, 
and rose from the surface of the sea, passing over our heads in 2 
great tongue-shaped mass, which in a few minutes was directly 
above us. Then stones, some as large as a chestnut, began to 
