August 26, 1886] 
NATURE 389 
men had a larger number of genuine admirers, or 
gathered around them a wider circle of sincere and at- 
tached friends. And not alone to the fields in which he 
himself worked did he extend his interest and sympathies. 
Amid the labourers in very different departments of 
thought he found some of his most cherished friends— 
frequent and always welcome guests at his hospitable 
home. For these, and for all who had enjoyed the privi- 
lege of his friendship, the sorrow at his loss will be 
softened by the ennobling memory of his life. 
Gro. J. ALLMAN 
BRITISH ASSOCIATION, SECTION B: DISCUS- | 
SION ON THE NATURE OF SOLUTION 
(4 may perhaps be convenient to those chemists who 
have announced their intention of joining in the pro- 
posed debate in Section B, at the approaching meeting of 
the British Association, that, having accepted the invita- 
tion of the President to open the discussion, I should 
indicate briefly the general nature of the subjects upon 
which I shall offer some remarks, and the order in which 
I shall probably take them. 
After an historical sketch of the theories which have 
been framed with the object of explaining the constitution 
of saline and other solutions, the phenomena of solution 
will be dealt with somewhat as follows :— 
Thermal and volume changes occurring in the act of 
solution and their mutual relations. How far and under 
what circumstances are thermal and volume changes to 
be considered as indicating chemical change? 
The molecular volumes of saltsin solution. The specific 
heat and vapour pressures of salt solutions. The relation 
of solubility to molecular volume, to fusibility, and to the 
composition of the liquid. 
Action of solids and especially of porous bodies on 
solutions. Phenomena of supersaturation. 
What is chemical combination, and is there any criterion 
by which it may be distinguished from adhesion or 
mechanical combination ? 
In consequence of the very wide-reaching character of 
the subject, it will not be possible to take up the question 
of solution except as relating chiefly to solids, and 
especially salts, in water. For the same reason I cannot 
fully discuss the phenomena of absorption-spectra nor 
generally the action of solutions upon light, but I hope 
some of those chemists who have worked on this part of 
the subject will be present, and will give us the benefit of 
their experience. 
There will of course be a great number of questions 
incidentally touched upon in my opening, which may well 
form the basis of remarks from other speakers, such as— 
How is saturation to be explained, ze. why is there 
generally a limit to solubility ? 
Is there any general connection between solubility and 
atomic weight in a series of compounds in which only 
one constituent varies ? 
What becomes of water of crystallisation when’ a salt 
containing water is dissolved in water ? 
WILLIAM A. TILDEN 
The Mason College, Birmingham 
THE RECENT VOLCANIC ERUPTIONS IN 
NEW ZEALAND 
WE have been favoured by Dr. Hector, F.R.S., 
: Director of the Geological Survey of New Zealand, 
with a copy of a Preliminary Report drawn up by him for 
the New Zealand Government regarding the volcanic 
eruptions of last June in the North Island. It is grati- 
fying to find that the hope expressed in NATURE (p. 322) 
has been so promptly fulfilled, and that the investigation 
competent an observer as Dr. Hector. The following is 
his Report, but it is merely a preliminary outline, and will 
no doubt be followed by much ampler details. 
“Colonial Museum of New Zealand, Wellington, 
June 23, 1886 
“According to instructions from Government, I pro- 
ceeded to Tauranga on the evening of Thursday, the 1oth 
instant, in the colonial gunboat A/ézemoa, and arrived 
there on Saturday afternoon. At Tauranga I engaged 
the services of Mr. Spencer, a skilful landscape photo- 
grapher, and on Sunday our party, seven in number, 
drove to Rotorua by the Oripi Road, the ordinary route 
by Te Puke being blocked On Monday I proceeded to 
Wairoa with Captain Mair, who joined the boat expedi- 
tion, which had been organised to search the Native 
settlements on Tarawera Lake. On the same day I sent 
my assistant, Mr. Park, to the south of the disturbed area 
by way of Kaiteriria; and on Tuesday, following the 
same route, I examined the vicinity of Rotomahana, Mr. 
Spencer, with his camera, accompanied me everywhere, 
so that a series of well-selected views of the eruption and 
its effects was obtained. On Wednesday we started for 
Taupo, feeling anxious to complete the general view of 
the whole line of volcanic activity from Ruapehu to White 
Island, as alarming rumours were in circulation as to the 
extent of country that had been affected. By this route 
we also obtained a distant but interesting view of the 
newly-raised cones of Tarawera from the eastward. The 
incidents of the eruption have been so fully described by 
the Press that it is unnecessary for me to refer to them in 
this preliminary report, the chief object of my rapid 
inspection having been to ascertain the exact locality, 
nature, and extent of the outbreak, and its probable 
consequences to the district. A complete geological 
examination of the district has therefore been deferred 
until a more favourable season for field-work, and until 
the volcanic activity has sufficiently subsided to admit of 
accurate observation. 
“The focus of the disturbance was ascertained to be in 
a line extending from seven to ten miles in a north-east 
to south-west direction from the north end of the Tara- 
wera Range to Okaro Lake (see plan.) The northern 
part of this line is occupied by the Tarawera Range. 
This range has three summits, the northernmost being 
Wahanga; the central, Ruawahia, 3605 feet alt.; and 
the southernmost, Tarawera Mountain proper. The 
southern part of the line previous to the outburst was 
a depression occupied by Rotomahana Lake, surrounded 
by low undulating country composed of pumice-sands 
and overspreading deposits of siliceous sinter, most of 
which were connected with active geysers, amongst which 
the most famous were those at the Pink and White 
Terraces. 
“From the most reliable evidence it appears that the 
outbreak commenced at ten minutes past two on the 
morning of the 10th, by an eruption from the top of 
Wahanga, attended by a loud roaring noise, and slight 
earth-shocks. In a few minutes this was followed by a 
similar but more violent outburst from the top of Ruawahia 
—the middle peak of the range, and after a short interval 
this phase of the eruption culminated ina terrific explosion 
from the south end of Tarawera Range, north-east of 
Lake Rotomahana. For nearly two hours this was the 
only phase of the eruption, and was accompanied by the 
ejection of vast quantities of steam, pumice-dust, and hot 
stones, forming huge towering clouds, illuminated by 
lightning flashes. 
“Tt was at this time also that a great crack or fissure 
(A C on plan) was formed along the east face of the 
Tarawera Range. I only had a distant view of this 
fissure from the eastward, but Mr. Percy Smith, the 
Assistant Surveyor-General, who had a near view from 
of the remarkable phenomena has been undertaken by so | the sides, reports that the whole east end of the mountain 
