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local phenomenon, or is be continued over a large district, I 

 could not decide from a single landing. Anyhow, the volcanic 

 zone with tuffs and scoriae is very conspicuous. 



Volcanic surface forms in the basalt are also to be found 

 in other places, for instance, on Dunholm, a little further S., 

 where the lava sheets show splendid flow-forms. 



Interesting is also a locality on the S. of Henry Peninsula. 

 Here lies a very fine series of varying, partly very irregular 

 sheets of basalt, mostly amygdaloidal. Avery prominent, yellowish 

 zone proved to be a crushed breccia, cemented together mainly 

 by zeolites, especially laumontite (see below). In the breccia 

 are also to be found veins of a lighter, presumably silicious 

 mass, also green efflorescences, which are perhaps coloured 

 by a copper-salt. Under it lies a compact basalt without 

 visible scoriaceous structure. I was much interested to find, 

 at the boundary between both these forms of rock , a hot 

 spring containing sulphuretted hydrogen and with a temperature 

 of 38° C, jutting out of the perpendicular mountain wall, ex- 

 pelling a quantity of vapours, and strongly marked also by the 

 rich green algous vegetation, which thrives in the warmish 

 water running down to the shore in the form of a little brook ^). 



.Microscopically examined, it turns out that all these varieties 

 are very closely related. All, without exception, are basalts, 

 composed of augite and lath-shaped plagioclase, often with 

 some ore, the minerals contained showing great variation in 

 quantity when compared with one another. Already macros- 

 copically one is struck by the rarity of fresh, doleritic or 

 coarsely crystalline forms, andithis is confirmed microscopically; 

 in none of the samples of the basalt sheets that I examined did 

 I find fresh olivine, althougt green transformations show that 



M The only warm spring hitherto known in Greenland is situated on the 

 Island of Unartok in SW. Greenland; its temperature is about 40° C. 



