NOVEMBER 15, 1906| 
NATURE 6 
on 
ttinguished from those of volcanic origin; seismic pheno- 
mena are often preceded and accompanied by magnetic 
edisturbances. This view was combated, however, by Prof. 
Lawson and Dr. Becker, while Mr. H. F. Reid held that 
the available data are quite insufficient for deciding the 
point. Dr. K. Renz (Breslau) next read a paper, ** Ueber 
-das Altere Mesozoicum Griechenlands,’’ adducing reasons 
why certain marbles hitherto referred to the Cretaceous 
might be transferred to the Trias. 
Several papers the titles of which appeared on the pro- 
gramme were abandoned or postponed owing to the absence 
-of their authors. 
It had been arranged that the meetings of the congress 
should take place only on alternate days, the intervening 
-days being devoted to sight-seeing and excursions, so the 
second meeting did not take place until the forenoon of 
Saturday, September 8, when Prof. Diener (Vienna) 
occupied the chair. The first business was a statement 
by Dr. Adams (Montreal) regarding the general geo- 
logical map of North America, of which copies (each con- 
sisting of four large sheets, scale 1: 5,000,000) had been 
previously distributed to the members. This map_ has 
‘been prepared in accordance with the instructions of the 
‘Geological Society of America, which at its last meeting, 
in Ottawa, appointed a committee (members:—J. C. 
Russell (president), J. G. Aguilera, Bailey Willis, F. 
Adams, C. W. Hayes) to carry the matter through. The 
“expense was borne by the Geological Survey of the United 
States, the Mexican Government assisting by purchasing 
a large number of copies for presentation to the members 
of the present congress. Explanatory notices are provided 
‘by Messrs. Bailey Willis and Aguilera.” The nomenclature 
adopted is that of the United States Survey, and at the 
meeting this called forth a certain amount of criticism 
‘from Prof. Lawson (California), especially with reference 
‘to the use of the term ‘‘ Algonkian.”’ 
The remainder of the forenoon meeting, and the greater 
part of the afternoon meeting, were devoted to papers and 
discussion on ‘*‘ The Climatic Conditions during the Geo- 
logical Epochs.’’ The first contribution was made by Prof. 
J. W. E. David (Sydney), who discussed the glacial 
phenomena more especially of Australia, but also of India, 
South Africa, and South America. He was followed by 
Prof. Frech (Breslau), ‘‘ Ueber die Klimainderungen der 
-geologischen Vergangenheit.’’ From Palaozoic times up 
‘to the present there has always been a correlation between 
the climatic evolution of the earth and the proportion of 
carbonic anhydride and of water vapour present in the 
-atmosphere. Increases are due to volcanic exhalations, 
and diminutions to the formation of organic and, more 
-especially, of inorganic compounds. 
At the afternoon meeting of September 8, presided over 
‘by Prof. Frech, the general discussion was opened by 
Dr. E. Philippi (Berlin), and was continued by Messrs. 
*C. Burckhardt (Mexico), Frech, A. Rothpletz (Munich), 
*C. Diener, F. vy. Kerner (Vienna), Vorwerg (Herischdorf), 
A. P. Coleman (Toronto), and M. Allorge (Oxford); it is 
‘impossible, however, to give in the space now available 
even a short review of the discussion. The general results 
were summed up by the chairman, who considered that the 
‘following might apparently be accepted as well-ascertained 
facts :—the existence of a Permo-Carboniferous Glacial 
epoch; uniformity of climate during the Triassic and the 
Jurassic; the existence of zones of climate since the 
Middle Cretaceous, and a gradual diminution of tempera- 
ture during the Ternary and the Quaternary. 
This was followed by a paper by General L. de Lamothe 
(Grenoble) on ‘‘ Le Climat de l’Afrique du Nord pendant 
‘les Periodes Pleiocéne et Pleistocéne,’’ after which Prof. 
‘Stefanescu (Bucharest) gave a description of the skeleton 
of Dinotherium gigantissimum (Stefanescu), a new species 
ediscovered by him in 1888, and, finally, a study by Mr. 
Hilgard on ‘‘ The Causes of the Glacial Epoch” was 
contributed by Mr. M. Manson. 
The discussion on climatic conditions was reopened at 
the next meeting on Monday, September 10, when Dr. 
Becker presided. The point chiefly dealt with was the 
question as to the causes which led to extensive glaciation 
‘in parts of the earth’s surface where, under present con- 
_-ditions, an extensive snowfall is difficult to explain. The 
rincipal speakers were Messrs. W. M. Davis (Harvard), 
NO. 1933, VOL. 75] 
He i Bairchild 
David, and Frech. 
The remainder of the forenoon meeting on September 10, 
and part of the afternoon meeting (under the presidency 
of Prof. Tschernyscheff, St. Petersburg), were devoted to 
the subject of the formation of ore deposits, but many of 
the papers announced in the programme were abandoned. 
The first paper was by Mr. H. F. Bain (Illinois), on 
“Some Relations of Palaeography to Ore Deposition in 
the Mississippi Valley,’’ and led to some discussion as to 
the possibility of soluble salts of the heavy metals reach- 
ing the sea, there to be deposited by secondary, action. 
In his communication ‘‘ Sur la Relation entre | Etat pro- 
pylitique (Griinstein) des Andesites et la Genése des Filons 
liés A cette Roche,’’ Mr. B. yv. Inkey (Dométori) showed 
that the formation of the Griinstein which is so character- 
istic for the metalliferous veins of Hungary (and also, as 
Prof. Kemp pointed out, for those of the Sierra Nevada) 
is due chiefly to the chloritisation of the black augite and 
hornblende of the original andesite, and results from an 
action quite different from the kaolinisation along the veins 
(Rochester), Heilprin (Washington), 
themselves. This paper also gave rise to considerable dis- 
cussion. Prof. J. F. Kemp (New York) read a paper on 
““Ore Deposits at the Contacts of Intrusive Rocks and 
Limestones, and their Significance as regards the General 
Formation of Veins,’’ holding that the evidence indicated 
that part of the material for the mineral formation must 
have been brought in by water, which probably came from 
the intrusive magma. Other papers, which, however, did 
not give rise to much discussion, were contributed by 
Mr. Villarello (Mexico), ‘‘ Sur le Remplissage de quelques 
Gites metalliféres’’; Mr. W. H. Weed (Washington), 
““The Origin and Classification of Ore Deposits ’’; and 
Mr. Lindgren, ‘‘ The Relation of Ore Deposits to Depth.” 
Three papers illustrated by lantern pictures followed ; 
the first, by Mr. G. Andersen, dealing with the Swedish 
Antarctic Expedition, was contributed by Prof. Sjogren; 
the second, by Mr. Heilprin, dealt with the eruption at 
Martinique; whilst the third, by Dr. Tempest Anderson 
(York), dealt with that of St. Vincent. 
At the Wednesday’s meeting, September 12, presided 
over by Prof. Rothpletz, Prof. Kéonigsberger (Freiburg 
i. B.) read a paper, ‘‘ Ueber den Verlauf der Geoisothermen 
in Bergen, und seine Beeinflussung durch Schichtstellung. 
Wasserliufe und chemische Processe.’’ In the course of 
this he showed how, by means of a special apparatus 
devised by him, variations of underground temperature 
might be measured accurately, and indications obtained 
by which voleanic eruptions might be foretold. This led 
to a discussion in which Messrs. Becker, Schmidt (Stutt- 
gart), Giinther (Munich), and von Kerner (Vienna) took 
part. Thereafter Prof. Keilhack (Berlin) discussed the 
mode of formation of the onyx bed at Etla, Oaxaca 
(Mexico), and Mr. Diaz (Colima) gave particulars regard- 
ing the volcano of Colima, pointing out that there was. 
apparently, a periodicity in its activity. It was announced 
that the discussions on ‘‘ The Nomenclature and Classifi- 
cation of Rocks ’’ and on ‘‘ The Relations between ‘ Tec- 
tonique’ and Eruptive Masses *? would not be proceeded 
with. 
Various resolutions of the council were approved, 
namely, that the new subject for the Spendiaroff prize be 
““The Description of a Fauna with Reference to its 
Geological Evolution and its Geographical Distribution 78 
re-approval of the proposal to create a model institute of 
geophysics; the institution of a special commission to 
study the variations of the geothermal degree. 
The concluding items were, a lecture by Mr. Sabatini 
(Rome) on “La derniére Eruption du Vésuve,’’ and 
another by Dr. Tempest Anderson on the same subject ; 
these were accompanied by lantern illustrations. 
There was no afternoon session. 
The last meetings took place on Friday, September 14. 
At the forenoon session, Mr. C. W. Hayes (Washington) 
presiding, the most important matter dealt with was 
‘““The Earthquake of San Francisco,’’ introduced by 
Prof. Lawson, whose paper was followed by a discussion 
in which Messrs. Frech, T. L. Ransome (Washington), 
and H. F. Reid (Baltimore) took part. The other papers 
were on ‘Interglacial Periods in Canada,”’ by Prof. 
Coleman; ‘‘ Geologic Classification in the North-Central 
