﻿108 



PEOP. E. W. SKEATS ON THE 



[Feb. 1905, 



The Drei Zinnen Area. 



No. 

 71a. 



70 . 



71 . 



was not in place, 

 of insoluble residue. 



The three specimens were col- 

 lected during the descent of 

 the upper part of the Bienz 

 Thai, on the western flanks of 

 the Drei Zinnen. No. 71 a 

 All three specimens represent dolomites devoid 



OaC0 3 . 



MgC0 3 . 



Insol. res. 



Per cent. 



Per cent. 





547 



453 





54-3 



45-7 





55-0 



45-0 





It now remains to record, for comparison with the Schlern 

 Dolomite, analyses from rocks below and above it. 



Analyses from Beds below the Schlern Dolomite. 



Wengen Limestone. 



CaC0 3 . 



Per cent. 

 64-9 



No 

 22 



MgC0 3 . I Fe 2 3 . I Insol. res. 



Per cent} Per cent.l Per cent. 



4-7 4-62 20-84 



The Wengen Beds of 

 the Seiser Alp include 

 some limestones, and 

 an analysis of one of 

 them (No. 22) shows that a very high percentage of insoluble 

 residue and less than 5 per cent, of magnesium-carbonate are 

 present. 



Buchenstein Beds. 



Immediately below the dolomite of the Schlern, Langkofl, and 

 Marmolata comes a nodular siliceous limestone — the Buchenstein 



Limestone. Two analyses were 

 made from this horizon. ]STo. IS 

 is from the base of the Schlern, 

 above Bad Ratzes ; No. 88 from 

 the Gader Gorge, in the Yalley of 

 Abtei, about 1 mile north of St. Leonhard. Both analyses show a 

 high percentage of insoluble residue and a small amount of 

 magnesium- carbon ate. 



No 

 18 



CaC0 3 . I MgC0 3 . Residue. 



Per cent. Per cent.l Per cent. 

 89-2 3-4 7-33 



817 8-6 I 9-73 



Mendola Dolomite. 



The Mendola Dolomite occurs only in certain districts, and 

 represents a local modification of the Upper Muschelkalk. No. 19 



is from the Schlern massif, below 

 the Buchenstein Limestone and 

 above Bad Batzes. No. 26 is 

 from the Pufels Schlucht, north of 

 the Seiser Alp, and leading into the 

 Groden Yalley. The insoluble residue in each case approaches 

 1 per cent., and the magnesium-carbonate falls short of that in a 

 theoretical dolomite by 3 or 4 per cent. 





CaC0 3 . 



MgC0 3 . 



Residue. 



No. 



Per cent. 



Per cent. 



Per cent. 



19... 



58-2 



40-9 



•93 



26... 



57-4 



41-9 



•73 



