DECEMBER 24, 1903] 
NATURE 
IOI 
Geological Society, December 2.—Sir Archibald Geikie, 
F.R.S., vice-president, in the chair.—Notes on the garnet- 
bearing and associated rocks of the Borrowdale volcanic 
series, by the late Mr. Edward E. Walker. A detailed de- 
scription of sills and dykes of garnet-bearing rocks in the 
Langstrath Valley is given, and similar rocks are described, 
occurring as dykes and sills around the Eskdale granite 
and the Buttermere granophyre, and also in the Armboth- 
Helvellyn area. They consist of diabase, porphyrite, and 
granophyre. The rocks appear to be related to the Esk- 
dale and Buttermere masses of intrusive rocks. Garnets 
are also found in a group of rocks below the great banded 
ashes and breccias of the Scawfell group, and in the rocks 
of the Scawfell group itself. These rocks often have a 
streaky structure, which exhibits types resulting from in- 
filtration along planes of weakness, lamination of ash, flow 
of igneous material, and dynamic action on included frag- 
ments. The banded ashes of the Scawfell group also con- 
tain garnets. The garnets are of the almandine type. 
They often have a ring of felspar around them, which, when 
the intrusive rocks are studied, suggests that the mineral 
is original; but similar rings occur around garnets in the 
ashes, showing that the felspars may be formed in solid 
rock.—A contribution to the Glacial geology of Tasmania, 
by Prof. J. W. Gregory, F.R.S. After giving an analysis 
of previous contributions to this subject, the author describes 
the evidence obtained by himself personally in the northern 
portion of the island. The town of Gormanston stands on 
a Glacial moraine of recent geological age, formed later 
than the excavation of the Linda Valley, and occurring as 
a bank projecting from the southern side of the valley. 
The moraine is composed of typical Boulder-clay, and be- 
hind it are bedded clays, probably accumulated in a glacier 
lake above the moraine dam. An erratic of fossiliferous 
limestone, scratched all over and partly polished, is 
mentioned, while a railway has cut through an enormous 
boulder of black Carboniferous Limestone 16 feet in length. 
The northern face of Mt. Owen appears to be ice-worn to 
the height of about 1900 feet, while the base of the Glacial 
deposits is not more than 700 feet above the sea. The 
general evidence suggests that the Eldon Range and the 
central plateau formed the gathering-ground of the ice 
which flowed westward and south-westward. A map is 
given to show the range of Pleistocene glaciation so far 
as it has been recorded, and also to indicate localities of 
the glacial deposition, which probably dates from the 
Carboniferous period. The lowest level at which evidence 
of Pleistocene glaciation has been found is 400 feet on the 
Pieman River. Many of the deposits are little more altered 
than those of northern England, despite the heavy rainfall, 
and the aspect of some of the rock-scoring is very recent. 
Entomological Society, December 2.—Prof. E. B: 
Poulton, F.R.S., president, in the chair.—Mr. G. T. 
Porritt exhibited, on behalf of Mr. T. Ashton Lofthouse, 
a specimen of Xylophasia zollikoferi taken at Sugar, near 
Middlesbrough, Yorkshire, on September 26 last. He said 
he believed that this was only the second specimen which 
had been recorded as having been taken in Britain. Mr. 
McLachlan, F.R.S., said the strongest evidence existed that 
a very large immigration of insects from the nearest Conti- 
nental coast took place during the exceptional (for this year) 
spell of warm and calm weather prevailing towards the end 
of September, and he was of opinion that the specimen of 
Xylophasia zollikoferi, taken by Mr. Lofthouse in York- 
shire, formed an item in this migratory swarm. Mr. Eagle 
Clarke had witnessed such immigration when staying on 
board the “ Kentish Knock ”’ lightship for the purpose of 
studying bird-migration. He had witnessed a considerable 
immigration of Vanessa cardui, for instance, amongst 
many other insects, and not the least remarkable of his 
observations was the fact that V. cardui flies at night during 
migration as well as by day. Mr. McLachlan remarked 
that the laws. governing migration in insects were at pre- 
sent little understood, and urged upon entomologists the 
necessity of obtaining a clearer insight into their working. 
—Mr. Malcolm Burr exhibited, and remarked on, a speci- 
men of Dinarchus dasypus, Mllig., belonging to a family 
of five or six species confined to the Balkans.—The presi- 
dent exhibited a series of photographs sent by Mr. A. H. 
Thayer to illustrate his views on the significance of the 
NO. 1782, VOL. 69] 
colours and patterns of butterflies’ wings. The insects had 
been photographed on masses of foliage and flowers, and 
it was obvious that the dark ground-colour harmonised 
with the dark shadow behind and under the vegetation, 
while the light markings stood out as conventionalised re- 
presentations of single flowers and flower-masses.—The 
president also exhibited the eyeless imagines and pupa- 
cases of Ennomos autumnaria, in illustration of his remarks 
at the meeting on November 18. Imagines produced by 
unblinded larvee were also shown for comparison.—The 
Rey. Francis D. Morice read a paper entitled ‘* Illustra- 
tions of the Male Terminal Segments and Armatures in 
Thirty-five Species of the Hymenopterous Genus Colletes.”’ 
Faraday Society, December 8.—Prof. A. K. Huntington 
presided.—The total and free energy of the lead accumu- 
lator, by Dr. Lehfeldt.—Bitumen in insulating composi- 
tions, part i., by Mr. J. A. Sutherland. Little or no 
trustworthy data have been published as to the use of 
bitumen for ‘electrical purposes. The chief source of bitu- 
men is Trinidad Lake, where there is estimated to be a 
quantity of nine million tons, which appears to be renewed 
to the extent of 20,000 tons annually. More than 150,000 
tons are exported yearly. Bitumen is also found in 
Venezuela, California, and on the shores of the Dead Sea; 
it occurs in some limestone (asphalt) as an impregnation, 
about ro to 15 per cent. being present, but it does not 
pay to extract it from this source. Its physical and chemical 
properties and constitution, which are fully dealt with in 
the paper, prove it to be infinitely superior to gas or coal 
tar for insulation and durability. The object of the present 
Paper is to invite discussion and the views of electrical 
engineers to assist the author in the completion of his ex- 
periments, and to enable him to draw up a satisfactory 
definition of bitumen, so that users may secure the best 
results from its valuable non-hygroscopic and insulating 
qualities. 
Royal Meteorological Society, December 16.—Capt. D. 
Wilson-Barker, president, in the chair—Mr. W. Marriott 
gave some account of the meteorological work of the late 
Mr. James Glaisher, F.R.S. Mr. Glaisher was best known 
to the public for the twenty-eight balloon ascents which 
he made for scientific purposes in 1862-9 on behalf of the 
British Association committee. The highest ascent was 
that from Wolverhampton on September 5, 1862, when the 
height of about seven miles from the earth was reached. 
Mr. Glaisher was rendered insensible, while Mr. Coxwell’s 
hands were frozen, and he was only able to open the valve 
of the balloon by tugging at the rope with his teeth.—A 
paper by Mr. J. R. Sutten on certain relationships between 
the diurnal curves of barometric pressure and vapour tension 
at Kenilworth (Kimberley), South Africa, in the absence 
of the author was read by the secretary. 
Paris. 
Academy of Sciences, December 14.—M. Albert Gaudry 
in the chair.—The principal characters of band and line 
spectra, by M. H. Deslandres. The two classes of spectra 
have one important property in common, they are both 
formed by the repetition of similar groups of lines or bands, 
but there are numerous points of difference, the repetition of 
the groups being regulated by functions of different form 
in the two cases; line spectra are also affected by alteration 
of pressure and by an intense magnetic field, whilst band 
spectra are unaffected under similar conditions. The ex- 
periments made by the author, especially on the line and 
band spectra of nitrogen, are not in agreement with the 
usual view that line spectra correspond to the vibrations 
of the atoms, and band spectra to those of molecules. The 
views of Runge are also criticised, and the need of further 
experimentai worl: pointed out.—Spectroscopical studies of 
the blood made on Mt. Blane by the late M. Henocque, 
by M. J. Janssen.—The discovery of cones of Sequoia and 
of pine in the Portland strata in the neighbourhood of 
Boulogne-sur-Mer, by MM. R. Zeiller and P. Fliche.— 
On the suppression of magnetic hysteresis by an oscillating 
magnetic field, by M. P. Duhem. The author applies the 
theories previously developed by him to the experimental 
results of M. C. Maurain. M. Marconi has attributed the 
effects produced in his receiver to the suppression of 
magnetic viscosity, and M. Tissot to the suppression of 
