46 SMITHSONIAN INSTITUTION 



these is often a tedious and disagreeable task. The sticky, tenacious 

 clays are saturated with brine and to collect the crystals we often 

 found it necessary to lie prone in the mud and alkali. The material 

 so collected, however, is of interest and importance for the study of 

 these little known occurrences. 



The mineralogical information obtained during the trip adds much 

 to our knowledge of the boron minerals, a group that has received 

 little scientific attention. The specimen material acquired augments 

 the fine collections of this character already in the National Museum. 

 Some striking groups of fine crystals were collected for exhibition. 



For the privilege of visiting many of the mines, acknowledgment 

 is due Messrs. Zabriskie, Rasor, Osborne, and Gower of the Pacific 

 Coast Borax Company, as well as a number of other friends who have 

 contributed both to the success of the undertaking and to the comfort 

 of the members of the expedition. 



