^T. 39.] TO GEORGE ENGELMANN. 373 



plan on which it was commenced seven hundred or 

 eight hundred years ago, and in which the choir was 

 finished, and the transepts and nave commenced. It 

 is most grand ; the grandest thing we ever saw, though 

 the nave bears only a temporary roof, at thirty or 

 forty feet less than the full height. The ancient 

 stained glass comes fully up to one's expectation. I 

 have never seen the like. 



We went up to Poppelsdorf ; such charming and 

 picturesque view of the Siebengebirge (seven moun- 

 tains) and the Godesberg, etc., from the professor's 

 windows and the Botanic Garden ; the museums rich 

 and curious, and parts of the old chateau in which 

 they are (now surrendered to the university) not less 

 so. The botanical professors, Treviranus 1 and Dr. 

 Roemer, very kind ; some collections to be made ready 

 here for me to examine when we come back, so that I 

 must then spend a day here. . . . 



TO GEORGE ENGELMANN. 



GENEVA, August 16, 1850. 



We went up the Rhine to Coblenz, Bingen, and 

 Mayence ; thence to Frankfort. By some mistake in 

 the post office in giving me the address, your letter to 

 Dr. Fresenius 2 I took to a law-doctor Fresenius, who 

 was away in Switzerland. So I gave up all hopes of 

 seeing him, and we fell to seeing the sights by our- 

 selves, when, a few hours before we had arranged to 

 go to Heidelberg, the true Dr. Fresenius came in. 

 We may see him again on our way back. We went 

 to Heidelberg, for an hour or two only. . . . 



1 Ludolf Christian Treviranus, 1779-1864 ; professor of botany in 

 Bonn. 



2 J. B. G. W. Fresenius, M. D., 1808-1866. Wrote many contribu- 

 tions to mycology. 



