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NATURE 
[Fune 25, 1885 
——— EEE ee nL, LL. LL. 
peninsula—in the neighbourhood of Clynnog and of Aberdaron. 
Lastly, he described a very remarkable picrite boulder, disco- 
yered by Dr. Hicks, which rests on ‘‘ Dimetian” rock at Porth- 
lisky near St. David’s.—Sketches of South-African Geology ; 
No. 2, a sketch of the gold-fields of the Transvaal, South Africa, 
by W. H. Penning, F.G.S. The gold-fields of the Transvaal 
have been defined as covering nearly all the eastern and 
northern districts of the State, though but a small portion of the 
area is productive. In this paper the author described only the 
Lydenburg and De Kaap gold-fields, leaving those of Pretoria 
and Marabastadt for a future communication. The auriferous 
region is known to extend 350 miles to the northward beyond 
the Limpopo River, so that the gold-bearing rocks are found 
throughout at least 74 degrees of latitude and 3 of longitude. 
The area of the two gold-fields mentioned, comprising together 
absut 3000 square miles, was defined ; and the author, after 
noticing some old gold-workings, proceeded to give an account 
of the physical features of the country. He especially called 
attention to the circumstance that most of the rivers rise to the 
west of the highest range, and flow eastward through it. The 
oldest gold-bearing rocks consist of unfossiliferous schists, shales, 
cherts, and quartzites, classed by the author as Silurian. 
Amongst these a great mass of coarse granitic rock is intruded, 
consisting of quartz and felspar, with but little, if any, mica. 
This granite, in the De Kaap valley, forms an ellipse seventeen 
miles long by ten broad, with a narrow northerly prolongation. 
Both the granite and the stratified rock are traversed by intrusive 
dykes, chiefly of diorite. These beds have been much disturbed 
and then cut down, probably by marine denudation, to a level 
plain 1700 or 1800 feet above the sea. Upon them rest uncon- 
formably a great sequence of conglomerates, sandstones, and 
shales, the ‘‘ Megaliesberg beds” of a former paper, but now 
provisionally classed as Devonian. These rocks also are traversed 
by dykes of diorite and other kinds of trap. The ** High Veldt 
beds” overlie the ‘ Devonian” with some unconformity. 
Several sections and observations illustrative of these facts were 
described, and details were given of the different gold-mines in 
each of the great systems noticed, and also in alluvial deposits. 
Tt was shown that much gold was derived originally from veins 
in the older or Silurian rocks, and that some of that met with in 
the newer system occurred in conglomerates or other detrital 
beds. But there are also gold-bearing quartz-veins intersecting 
the latter.—On some erratics in the boulder-clay of Cheshire, 
&c., and the conditions of climate they denote, by Charles 
Ricketts, M.D., F.G.S. 
Royal Meteorological Society, June 17.—Mr. R. H. Scott, 
F.R.S., President, in the chair.—Lieut. A. Leeper, R.N., was 
elected a Fellow of the Society.—The following papers were read : 
—A few meteorological observations made on a voyage up the Nile 
in February and March, 1885, by Dr. W. Marcet, F.R.S. The 
author, on a voyage up the Nile from Cairo to Assouan, made a 
series of meteorological observations, and in the present paper 
gives the results of those relating mainly to nocturnal radiation 
and the temperature of the water of the Nile.-—The mean direc- 
tion of cirrus clouds over Europe, by Dr. H. H. Hildebrandsson, 
Hon.Mem.R.Met.Soc. The author has collected a number of 
observations on the movements of cirrus clouds over various 
parts of Europe, and after discussing them has arrived at the 
following results: (1) the mean direction at all stations lies 
between south-west and north-west ; (2) in winter the cirri come 
from a more northerly direction, and in summer from a more 
southerly ; (3) in winter the northerly component is greater on 
the Baltic and the north coast of the Mediterranean ; (4) the mean 
directions of the upper currents nearly coincide with the mean 
tracks of storm-centres ; (5) the upper currents of the atmosphere 
tend in general to flow away from those areas in which a baro- 
metrical depression exists at the earth’s surface towards those in 
which there is an elevation of pressure.—On the influence of 
accumulations of snow on climate, by Dr. A. Woeikoff, 
Hon. Mem. R. Met.Soc.—Note on the weather of January, 1881, 
by Mr. E. Harding, F.R.Met.Soc. It will be remembered that 
the weather of January, 1881, was remarkable for the prolonged 
and exceptionally severe frost, the heavy gale of the 18th and 
19th, and the snowstorms. The author has prepared isobaric 
charts for the North Atlantic and adjacent continents for January, 
1881, and compared it with similar charts for January in other 
years. He shows that the severe weather in 1881 was due to a 
reversal of the normal conditions, the atmospheric pressuie being 
high in the north and low in the south.—Results of meteoro- 
logical observations made in the Solomon Group, 1882-84, by 
Lieut. A. Leeper, R.N.—Graphic hygrometrical table, by Mr. 
D. Cunningham, M.Inst.C.E., F.R.Met.Soc. 
Geologists’ Association, June 5.—Wm. Topley, F.G.S., 
President, in the chair.—A paper was read by Mr. Herbert 
Goss, F.L.S., on some recently-discovered Insecta and Arach- 
nida from Carboniferous and Silurian Rocks. The author 
stated that in 1879 only 103 fossil insects from the Carboniferous 
rocks of the whole world were known, but during the last five 
years a great number had been discovered, including about 1400 
from Commentry, France, a few from Saarbriick, Klein Opitz, 
Lugau, and elsewhere on the Continent of Europe, and a con- 
siderable number from various parts of the North American 
Continent. The specimens were enumerated, some of the most 
remarkable forms were referred to in detail, and attention was 
drawn to their affinities with existing types. Many of the speci- 
mens were of gigantic size and in a fine state of preservation, 
and whilst the majority of them appeared referable to forms 
allied to existing genera of Hemiptera, Neuroptera, and Ortho- 
plera, a considerable number consisted of synthetic types inter- 
mediate between these orders, uniting in themselves certain 
peculiarities of structure now characteristic of distinct orders. 
Attention was also called to the recent discovery of fossil scor- 
pions in the Upper Silurian of the Isle of Gothland and Scotland, 
and the wing of a cockroach in the Middle Silurian of Jurques, 
Calvados, France. Prior to these discoveries no remains of terres- 
trial animals had been obtained from any strata older than the 
Devonian, and the result of their discovery in Silurian strata 
was to leave the Zysecfa the oldest known class of land animals, 
and the Blattide the oldest family of insects. The evidence 
afforded by Palzeontology was therefore, as far as it went, in 
support of the views as to the origin of insects and the order of 
succession of the various groups previously arrived at from a 
study of the embryology of the class. 
EDINBURGH 
Royal Society, June 1.—Robert Gray, Vice-President, in 
the chair.—The Astronomer-Royal for Scotland showed the solar 
spectrum, as observed last year by him, drawn to scale 80 feet 
long. He contrasted it with the spectrum as seen by Fievez, 
and with that as seen by himself some years ago, a special 
object being to determine the effect of the present cosmic dust. 
—Prof. Tait gave a number of perfectly general methods of 
enumerating the amphicheiral knots of any order, and pointed 
out the curious fact that amphicheirals may in many cases be 
transformed into other amphicheirals, sometimes in more than 
one way.—Mr. Hugh Robert Mill, B.Sc., communicated a paper 
on the chemistry of Japanese lacquer (Urzsht), by Mr. Hiko- 
rokuro Yoshida, chemist to the Imperial Geological Survey of 
Japan. Lacquer juice was found to consist of a monobasic acid 
(Urushic acid), a small proportion of a nitrogenous diastatic 
matter, gum arabic, and water. The hardening of lacquer was 
shown to be due to the oxidation of the urushic acid to oxy- 
urushic acid by the action of the nitrogenous substance in the 
presence of air and moisture, a number of experiments distinctly 
proving that it was not a case of hydration. Coloured lacquers 
are made by the addition of metals, their sulphides, or oxides, 
to the juice, which exerts no action upon them, except in the 
case of voivo or black lacquer, the colour of which is due to the 
presence of urushiate of iron produced by the addition of iron 
filings to the juice.—In a paper on atmospheric electricity at 
Dodabetta, Prof. C. Michie Smith pointed out that the fore- 
noon observations show a mean curve of atmospheric potential 
rising to a maximum at about the period of maximum tempera- 
ture. There is probably a much less marked night maximum, 
with, of course, a minimum between each maximum, From 
observations made on some exceptionally fine days, an afternoon 
curve was constructed. The afternoon observations, however, 
were usually much modified by mists, but the important fact 
was established that the potential was regularly less than the 
normal in a dissipating mist, and much above the normal in a 
condensing mist.—The Astronomer-Royal for Scotland exhibited 
a series of star-photographs. 
Paris 
Academy of Sciences, June 15.—Note on MM. Paul and 
Prosper Henry's apparatus for photographing the heavenlybodies, 
by M. Mouchez. The author presented to the Academy the 
already executed chart of a section of the Milky Way, including 
about 5000 stars from the sixth to the fifteenth magnitude com- 
prised in the space between 2° 15’ right ascension and 3° declina- 
tion. To complete the representation of the 41,000 superficial 
