August 5, 1886] 
NATURE 
gists have called the “ solfatara stage.” New geysers 
might break out, rivalling or even surpassing those 
already active in the district, and the orifices of eruption 
might shift from place to place, involving considerable 
local disturbance in their transference ; but no one antici- 
pated that in this district a great explosion, like the most 
gigantic outburst of Vesuvius, was likely to occur. 
The magnitude of the explosion may be inferred from 
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several facts which appear in the newspaper reports. An 
observer at New Plymouth, on the west side of the island, 
150 miles from the scene of the disaster, saw the column 
of ashes rising far into the air, and computed its height 
to be not less than 22,000 feet. The noise of the ex- 
plosion is said to have been heard at Christ Church, a 
distance of some 300 miles. The ashes fell over a vast 
area of land and sea to the north and east of the vent of 
discharge. Vessels sailing even 130 miles away found 
NEW CRATERS, thus 
the air thick with fine dust, which settled on their decks. 
Near the scene of the explosion the depth of accumulated 
ashes, still quite hot, was found by some adventurous 
explorers, seeking to succour the poor Maoris, to be not 
less than 20 feet. Ata distance of 30 or 40 miles the 
deposit was still several inches thick, so stupendous must 
have been the amount of rock blown into powder by the 
great explosion of Tarawera. 
The materials ejected from that mountain appear to 
have consisted mainly of loose fragments of lava, cinders, 
ashes, and fine dust, with vast quantities of steam, while 
not improbably hot water and mudissued from the flanks 
of the volcano. So far as can be gathered from the 
narratives, there was no emission of lava, though, from 
the “flames” and ‘‘fire-balls” so generally referred to, it 
may eventually be found that molten lava flowed out 
somewhere on the sides of the mountain. . 
Not far from the base of the volcanic cone of Tarawera 
lay the warm lake and sinter terraces of Rotomahana. 
The treacherous nature of that district has been often 
remarked—its steam-vents, boiling pools, hot steaming 
soil, and eruptive geysers, not always remaining in the 
same places, but apt with no warning to break out at 
fresh points. This weird locality has been involved in 
the volcanic disturbances of the region, The famous ter- 
races have been blown into the air, and fragments of their 
sinter have been picked up among the dust and ashes of 
the surrounding country. The lake on the borders of 
which they stood has been ingulfed. On their site 
scores of mud-cones are vomiting forth stones and mud, 
and hurling clouds of steam into the air. New vents for 
the escape of steam and the outflow of volcanic mud have 
been opened all over the country, and the aspect of the 
landscape has been entirely changed. A scene of fairy- 
like beauty has been transformed into one of -loathsome 
desolation. Even if the volcanic activity calms down 
and the sinter springs can recommence their work of de- 
position, many generations must pass away before they 
can build up again such terraces as have been destroyed. 
The new features of the country will no doubt still prove 
attractive to tourists, but the marvellous staircases of Te 
Tarata are a dream of the past. 
Among the features of the eruption on which it is to 
be hoped that light will be thrown by the more detailed 
investigations of experts are the source and behaviour of 
the mud that overwhelmed the settlement of Wairoa. 
From the narratives of the survivors, showing that the 
houses were crushed in from above, the mud seems to 
have descended through the air upon the district, mingled 
with ashes and stones. Rain fell during the night, but 
the mud could hardly have been formed in the air by the 
mixing of the rain and dry ashes. It appears to have 
come down as liquid mud and was no doubt ejected as 
such from some neighbouring vent. The orifice of erup- 
tion could scarcely have been the great cone of Tarawera ; 
more probably there were many vents not only at Roto- 
mahana, but nearer to Wairoa, by which a large amount 
of mud was discharged over the surrounding district. 
Another question that will no doubt receive careful con- 
sideration relates to the movements of the air during the 
time of the eruption. Barometric observations at Rotorua 
and at places on the opposite sides of the island will be 
of much interest. From the newspaper accounts it is 
clear that a great atmospheric disturbance accompanied 
the eruption. About an hour after the great explosion a 
gale suddenly arose in the Rotorua and Wairoa district, 
and blew with such fury as to uproot and prostrate im- 
mense numbers of trees, and to strip off leaves and 
branches from those that were left standing. At Rotorua 
the direction of the hurricane was towards the scene of 
volcanic activity, as if the air were being drawn into the 
vortex caused by the explosion. A few hours later the 
gale as suddenly ceased and then ashes began to fall, 
borne northwards by some upper current of air. We 
