Letters to a Friend 



me if I do not drown this tendency towards ner 

 vous prostration by constant labor in working 

 up the details of this whole question. I have 

 been down from the upper rocks only three days 

 and am hungry for exercise already. 



Prof. Runkle, president of the Boston Insti 

 tute of Technology, was here last week, and 

 I preached my glacial theory to him for five 

 days, taking him into the canon of the valley 

 and up among the grand glacier wombs and 

 pathways of the summit. He was fully con 

 vinced of the truth of my readings and urged 

 me to write out the glacial system of Yosemite 

 and its tributaries for the Boston Academy of 

 Science. I told him that I meant to write my 

 thoughts for my own use and that I would send 

 him the manuscript, and if he and his wise sci 

 entific brothers thought it of sufficient interest 

 they might publish it. 



He is going to send me some instruments, 



and I mean to go over all the glacier basins 



carefully, working until driven down by the 



snow. In winter I can make my drawings and 



[ 107 ] 



