3/o Humboldt's Letters. 



on the philosophy of physical science. He was active 

 underground, more occupied with practical mining and 

 furnace operations than with geognostic researches ; 

 thorough in the observation of fact, cheerful, and satiri- 

 cal, but always with good taste, and not intolerant of 

 those who differed from him. His imagination was not 

 then specially directed to religious subjects. He was 

 generally popular, and a little feared at the same time, 

 as is so common where there is a consciousness of mental 

 superiority. His political opinions were liberal. It was 

 the period of the Congress of Pillnitz in our neighbor- 

 hood a time and a neighborhood which gave occasion 

 to political utterances. 



soe. 



HUMBOLDT TO 



BERLIN, April 25tfi, 1857. 



" THE gate of the oracle, the abyss of the archives of 

 state, analogies leading down to the depths of the sea." 

 This is inferior to the last letter. Rafael's manner is not 

 always the same. I am surprised to find that curiosity 



appears, to have led him to avoid seeing before the 



journey to Hanover ! Preserve the vapid letter, my dear 

 friend ! The bottom of the sea refers to a map of the 



