33^ 
The American Geologist. -^^^y- 1*^^^- 
glassy or dovitrificd? Has it flow structure? Is it vesicular, amygda- 
loidal. spherulitic? 
(b) A veinstone. — What mineral or minerals compose it? What has 
been the order of their growth or genesis? What is the country rock? 
Did it furnish the substances in the vein? What is the nature of the 
cavity in which the vein is deposited? What rock movements are 
shown? Is there any volcanic breccia? When did the vein form in 
relation to other structures or rocks? 
(c) A clastic rock. — What is it? A conglomerate? If so. what 
rocks form the pebbles ? What is the cement ? How was the conglom- 
erate formed? If a sandstone, what is it composed of? What is the 
cement? If a pelite, what is its structure, lamination, banding, or strat- 
ification? Are there fossils? 
(d) A metanwrphic rock. — What is its structure, composition? 
What was it originally? What has produced the metamorphism ? 
In any case, what is the attitude of the rock? strike, dip? Has it 
been jointed, folded, faulted, tilted, metamorphosed? Has it slaty 
cleavage? dip and strike of same? What is the age of the rock relative 
to others of diiTerent kind ? In what order do the secondary structures 
intersect ? 
JVhat lias been the succession of events in the area studied? 
The Spendiaroff Prize. — The following- letter may per- 
haps explain itself: Le Congres g-eologique international, clans 
sa seance generale dti 25 Aoiit 1900, a nomme membres de la 
Commission du prix international Spendiaroff: MM. Albert 
Gaiidry, president ; Marcel Bertrand, Sir Archibald Geikie, 
Karpinsky, Tscherneyschew, Zirkel et V'on Zittel. Cette Com- 
mission propose comme sujet de prix pour 1003: 
Rci'iic critique cs v.icthodcs dc classincat'wn dcs rochcs. 
Dans la seance du 20 Aoi'it 1900. le Conseil du Congees 
avait decide que les ouvrages presentes pour le concours seront 
envoves au Secretaire general du dernier Congres au nombre 
deux exemplaires au moins, et que I'envoi sera fait au phts tard 
une annee avant la session suivante. Le Conseil a decide aussi 
que le droit de priorite pour obtenir le prix appartiendra aux 
(Euvres traitant les sujets proposes par le Congres. 
Les envois doivent etre addresses a M. Charles Rarrois, 
Secretaire General du Congres geologique international. 62 
boulevard Saint-Michel, Paris. 
La valeur du prix est de 456 roubles, c"est-a-dire environ 
1.200 francs, d'apres I'indication de M. Karpinskv. 
En vous comnuuiiquant ces renseignements, nous avons 
Thonneitr de vous prier d'en faire part aux savants qu'ils pour- 
raient interesser. 
Wniillez. Monsieur, agreer re?<prcssion de nos sentiments 
les plus distingties. 
AiJJERT CiMDRv. Le President du Cong-res. 
CiiAKEES I") ARRois. Lc Secretaire general. 
