Conglomerate.^ hi Gneissic Terranes — A.WiucheU. 163 
erally recogaized as «. syenite. It has indeed passed almost 
b^ond the stag? of alteration in which traces of sedimentary 
bedding remain. Nor is there any considerable mass of crystal- 
line schists within less than five miles of Wonder island. The 
evidence for fra^mental origins is thus carried fully into the 
midst of those crystalline masses so commonly regarded as 
centres of molten eruption. 
The earliest mention which 1 iind recorded of any analogous 
phenomena in the old world is by Dr. Sauer of Leipzig.* In the 
valley of the Mittweida near Annaberg, and about twenty-five 
miles south of Chemnitz, occurs a section of crushed conglomer- 
ate intercalated among the gneisses and mica-schists distributed 
over that part of Saxony . This appears, from the accounts, 
quite analogous to the pebble-bearing beds of the Green Moun- 
tains. 1 avail myself of a description of this occurrence recently 
published by Professor Hughes.f The complete sequence was 
not observed, but the vicinity is generally underlaid by musco- 
vite schists and gneissic rocks. At Obermittweida, a grey 
feldspathic granular rock occurs, with apparently superinduced 
schistosity. In this were seen scattered pebbles of felsitic and 
quartzose rock which soon became so numerous that the rock 
was obviously a coarse conglomerate. 'Mn the conglomerate 
were fissile sandy beds which, even when crushed, were quite 
unlike the mica-schists which cropped out above and below.'^ 
According to a diagram given, the series of beds dip about 40**. 
In theorizing on the occurrence, professor Hughes remarks 
that ''there was plenty of room for, and strong probability of, 
a fault along the valley below the section." ''On the whole, I 
was inclined to believe," he says, "from an examination of the 
rock in the field, that the conglomerate might belong to quite 
newer beds caught in a sharp synclinal fokl." In support of 
this conclusion, he says: "The character of the two rocks, that 
is, of the gneissic series and the two beds associated with the 
* "Ueber Conglomerate in der Glimnierschiefer-formation des Sach- 
sischen ICrzgebirges" — ZfitHchrift Fi'tr die gesammten NaturwisnensrlinfteUy 
Band lii, S. 706, 1879. The occurrence is noted on the Geologische Spccial- 
karte von Sachen, Massstab 1-25,000, Section Elterlein, nebst zugehorigen 
Erlaiiterungen. Prof. Justus Roth of Berlin, published a paper on these 
conglomerates in 1888, in Sitzungsherichte der Kql. Preu.1.9. Akad. der Wia- 
semcJi. zu Berlin, 1883, (Physikal-mathemat. Klasse,) xxviii, 14 Mai; and 
he later mentioned tbem in Allqemeine u. Chemigche Geol., ii, Bd., S. 427- 
428, Berlin, 1887. Roth gives a full account, copied from Sauer. 
t Quar. Jour. GpoI. 80c. Lond. xliv, Feb. 1, 188S, pp. 20 24. 
