272 SALMONIA. [NINTH DAT. 



quadrant iris on its spray are not brighter than those 

 of its stream and foam. 



ORN. We have now followed this water at least 

 thirty miles, and wherever we have seen it, it has 

 always displayed the same characters of clearness and 

 rapidity of green stream and white foam; and we 

 have traced it from the snowy mountains of Styria 

 to the plains of Upper Austria, where it serves to 

 purify the darker Danube. How is it, that it has 

 preserved its transparency, though so many of its 

 tributary streams have been foul, either from the 

 thunder storm, or from the sudden melting of snows ? 



HAL. The three small lakes and the two larger 

 ones, which are in fact its reservoirs, are the cause of 

 this. The Griindtl See furnishes its principal stream, 

 and this lake is fed by two others Toplitz See and 

 Lammer See ; and the tributary streams, which unite 

 at Aussee, from Alten Aussee and Oden See, though 

 one is blue and the other yellow, yet combine to give 

 a tint, which is nearly the same as that from the 

 stream of the Griindtl See, and which the river retains 

 throughout its course. Yet I have seen even this 

 river very foul, but only in a part of its course, below 

 Ischel. I was once at that place, when the thunder 

 storm of a night having washed the dust of the roads 

 into the river, it was extremely turbid from Ischel 

 to the Traun See. It rendered the upper part 



