American Museum of Natural History, 



New York City. 

 Hon. Clarence King, THredor: 



8iR: In compliance with your in.stnictions of March 6, 1880, directing- 

 me to report upon the Geology, Mineralogy, Chemistry, and Physics of the 

 CoMSTOCK Loue, I have the honor to transmit the accompanying report.' 



Although several reports on the Comstock Lode have appeared during 

 the past twenty years, the great extension of the mine workings and the 

 advances in geological science made it probable that additional information 

 of value would result from a reexamination of this famous ore-deposit. 

 Administrative dvities unfortunatel}' pi-evented you from undertaking the 

 study of the lower portions of the Lodk, the upper part of which you have 

 made so familiar to geologists. Under these circumstances, you did me the 

 hont)r to select me as your substitute; yet you did not abandon all share in 

 the investigation, since at every stage of it I have had the advantage of 

 your cordial support and wise counsel. 



Very respectfully, your obedient servant, 



GEO. F. BECKER, 



Geolo(jid-in-ckuigt. 



'Set! Si'coiid Aiiiiiial Report of the Director U. S. Geological Survey, page xl. 



(iii> 



