14 O. F. E'arris — Journey through Russia. 



the inhabitants of that manufacturing town were the first items on 

 the programme. The country seen on the way was flat or but 

 slightly undulating, with low hills occasionally ; the whole well 

 wooded and watered. Tbe Glacial clays passed through shortly 

 after starting were here and there covered by Post-Glacial clays and 

 littoral deposits containing Litorina, Cardium, Mytilus, Telltna, etc. 

 A ridge of considerable size was traversed by the railway at 

 Hyvinkaa, which proves to be a large terminal moraine. To the 

 north of that place moraine gravels predominate, and there are 

 several asar, a phenomenon which I intend to describe more 

 particularly at another stage of our journey. Then several lakes 

 come into view, and Tammerfors with its hilly scenery is reached. 



Tammerfors is situated on a narrow neck of land formed by an 

 " as," which separates the lakes of Nasijarvi and Pyhajarvi. The 

 former lake is about 58 feet above the latter, and the two are con- 

 nected by rapids, which in parts are very beautiful. The journeys 

 for the next two or three days were from that place as a centre, 

 a special train being always at our disposal. 



The neighbourhood of Tammerfors is excellent for studying the 

 Archgean rocks of Finland. The following divisions are recognized 

 by Mr. Sederholm ^ : — 



1. Post-Bothnian granite. 



2. Bothnian schists. 



3. Pre-Bothnian gneiss. 



In the last division, granites (essentially metamorphic), porphy- 

 roides, and closely foliated gneiss predominate. These latter, 

 according to Sederholm, are granitized mica-schists. All these rocks 

 crop out to the south of the town. 



We examined the foliated granite and mica-schist (on the after- 

 noon of our arrival) in a railway cutting at Siuro, about twenty 

 miles west of Tammerfors; and in a railway cutting to the west 

 of Suoniemi we had an opportunity of examining the mica-schist 

 highly plicated. The micro-structure of these and some other 

 Finnish rocks will presently be described. 



"We will turn now to the second division — the Bothnian schists, 

 which, as will be seen as this narrative proceeds, we examined at many 

 points. The local development of these is known as the Tammerfors 

 schists. They crop out in bands running east and west, the whole 

 being highly inclined and limited by the Pre-Bothnian gneiss on the 

 one hand and the enormous outcrops of the Post-Bothnian granite 

 on the other. These schists are often represented by phyllades,^ 

 which occasionally approach true argillites and sometimes pass 

 gradually into fine-grained mica-schists. The foliated arkose, which 

 Mr. Sederholm calls " leptite " (to be more particularly referred to 

 hereafter), occurs in this subdivision. So also do certain hornblende 

 (mostly uralite) schists (called porphyritoides), which were 

 originally volcanic tuffs, and sometimes have altered lavas inter- 

 calated between them. 



1 "Excursions en Finlande" (op. cit. supra), p. 2. 

 ^ This term is here used in its broad sense. 



