114 G. F. Karris — Journey through Russia. 



Perhaps the principal point of interest in this Archaean con- 

 glomerate is the change which some of the smaller fragments have 

 undergone. These adhere to each other for the most part, but here 

 and there is some well-developed granular quartz which acts as 

 a partial cement. The smaller clastic material consists of pieces 

 of plagioclase, fragments of uralitic augite, of quartz, and perhaps 

 of olivine. There has been a great deal of alteration and secondary 

 development in these fragments and the cement. That might have 

 been surmised from the condition of the augite, as just mentioned, 

 almost completely altered into uralite ; whilst the olivine is partially 

 changed to biotite and similar products. Rnnning through this finer 

 clastic material and the cement are roughly parallel lineations of 

 uralite, which is also seen bordering some of the larger pebbles. 

 It is accompanied by occasional minute flakes of biotite. 



The rough attempt to produce foliation in this conglomerate and 

 much of the change induced in the pyroxene was doubtless brought 

 about by the same processes w^hich converted the neighbouring 

 volcanic tuffs into uralite schists — for the conglomerates alternate 

 •with " beds " of these schists. 



Leaving this interesting little island we went across the bay 

 of Hormistonlahti, and landed to make a further examination of 

 the conglomerates and to inspect the uralite schists. The whole 

 of the rock is vertically disposed. These dai'k-green schists have 

 not been very much altered ; their foliation is not conspicuously 

 marked, though distinct enough when closely examined. The 

 volcanic ejectamenta are small, but the fragments, as seen under 

 the microscope, are sufficiently large to enable their basic character 

 to be distinctly made out, and they do not seem to have suffered 

 much in the conversion of the tuff into a metamorphic rock. As 

 will be readily understood, the uralite is for the most part orientated 

 and is the principal assistant in producing the foliate structure. 

 This mineral is most completely formed, and actinolitic needles 

 are not only spread all over it, but project from its sides in 

 chai'acteristic fashion. The needles also have a direction pai'allel 

 •with the folia and impart a semi-fibrous aspect to the mineral. 



A brisk walk along the beach enabled us to see that the uralite 

 schist was remarkably uniform in character for long distances ; I did 

 not observe any contortion in it. There appeared to be but few 

 exposures inland, a mantle of glacial beds spreading over the surface 

 of the ground and masking the solid beds beneath. But you cannot 

 see far in this part of Finland after you have left the lake-side. 

 The glacial beds give rise to a luxuriant vegetation, and though 

 the trees are not very tall thej' are sufficiently numerous and close 

 enough together to prevent one from observing much more than arises 

 along the immediate vicinity of the route traversed. 



Regaining the barges, we made an earnest attempt to negociate 

 the lake ; the little steamers did their best, and in a short time we 

 had covered 12 or 14 miles, in a northerly direction. Landing 

 again some few miles south of Teisko, opposite a grand section in 

 the glacial beds, full of boulders and small fragments of rock, 



