GAEL VON LINNE AS A GEOLOGIST NATHOEST. 723 



previous specimens. Some believe tlie marks to liave been caused by water, 

 because they greatly resemble a sandy sea or river bottom which had been 

 sculptured by the waves of the deep. * * * 



During his journey in Dalarne petroleum was also for the first 

 time discovered in Sweden, partly in the limestone quarries at Skar- 

 backa (in Osmunds Mountain), at Kiirfsasen in the parish of 

 Rattvik, and partly in the lime at Grana. Linne emphasized this 

 fact in his speech on the necessity of journeys of exploration within 

 the country thus: 



Perhaps you, my auditors, refuse to believe me when I say that in Dalarne 

 there are entire mountains saturated with petroleum, but let your doubts 

 be gone ! With my own eyes I have seen this, a fact never before seen or 

 heard of. * * * 



^ ^ ^ 4: -^ Hi H: 



The presence of petroleum in these localities gave occasion much 

 later, during the years 1867-1869, to several mining enterprises, 

 Avliich, however, as is well known, resulted in complete failure. 



Linne's observations on the Cambro-Silurian strata in southern 

 Sweden will be quoted in the succeeding chapter. Those concerning 

 Dalarne may, however, be cited here, as they are few in number and 

 have little in comm.on with those of Sweden. 



The mines at Bodback contain white or red lime, of which the red is so full of 

 white fossils that there does not seem to be space enough for another one. 

 Bauman's celebrated " Hohle," with its many foreign fossils, is as nothing com- 

 pared to this. Yet they are so little thought of that they are broken up and 

 used, instead of turf, in thatching roofs. 



lie then describes the most common fossil {Nautili articulati), 

 which clearly belongs to the genus Ortlioceras. 



Of what they are petrifications nobody knows * * *. They are not 

 cochleae, nor burbots, as some suppose. There are more fossils in the stones 

 than grains in porridge. * * * 



From the journey in Dalarne there is also an account of a large 

 pothole at Dala River, which is described, quite correctly, as having 

 been formed by the " continuous rotation of the stream." In the jour- 

 ney in Westrogothia mention is also made of the existence of a couple 

 of potholes in the neighborhood of Gothenburg. 



A couple of " giant pots " were seen not far from the strata and at a distance 

 barely equal to two gunshots from each other. They were cylindrical holes 

 bored deep in the mountain, and were 1 yard deep and 1 yard broad. One of 

 these pots was on the side of the mountain, on a gentle slope, but the hole was 

 vertical, regardless of the slope. 



During the journey in Skane another pothole is also mentioned: 



A Jetta well, as a " giant pot " is called in Westrogothia. was seen on Jette- 

 brunsliden, a hillside which one traverses on the way to Stockatorp. Here was 

 a pothole on the top of the cliff facing the sea, more than a yard iu dei)th and 



