228 



University of California Publications. 



[Geology 



elinopinacoid, but in general the base and pinacoid are in about 

 ecpial development. Most of the faces are brilliant and give good 

 reflections, but the elinopinacoid is invariably striated parallel 

 to the edge be. 



The habit and combination of forms of the stocky crystals is 



seen in plate 19, fig. 3. 



The forms observed on the crystals were : 



c (001) x (201) f (012) t (221) o (014) new 



b (010) 5 (021) <p (013) r (111) n (203) new 



m (110) e (011) s (223) 



In setting up the crystals for measurement the best results 

 were obtained by assuming the position a as the pole face and 

 zone be as first meridian. The readings in this position are given 

 in the columns </>' and p. With c as the pole face the transposed 

 angles corresponding to these readings are in columns <j>" and p" 

 obtained by means of the two formulae cos. p" = cos. </>' sin. p 

 and cot. </>" = sin. cf>' tan. p. 



Measured Calculated 









¥ 



P 



<; 



i" 



p" 





4> 



P 



c 



001 



0°00' 



90°00' 



0°00' 



0°00' 



0°00' 



0°00 



b 



010 



90 



00 



90 



00 







00 



90 



00 







00 



90 00 



m 



110 



89 



57 



42 



30 



47 



30 



90 



00 



47 



27 



90 00 







014 



19 



34 



90 



00 







00 



19 



34 







00 



19 23 





013 



25 



14 



90 



00 







00 



25 



14 







00 



25 07 



f 



012 



35 



15 



90 



00 







00 



35 



15 







00 



35 07 



e 



011 



54 



41 



90 



00 







00 



54 



41 







00 



54 35 



5 



021 



70 



41 



90 



00 







00 



70 



41 







00 



70 26 



X 



201 







00 



18 



1(5 



90 



00 



71 



44 



90 



00 



71 55 



n 



203 







00 



44 



28 



90 



00 



45 



32 



90 



00 



45 37 



t 



221 



70 



29 



44 



16 



47 



26 



76 



31 



47 



27 



76 29 



r 



111 



54 



32 



48 



25 



47 



27 



64 



17 



47 



27 



64 19 



s 



223 



43 



07 



53 



19 



47 



27 



54 



10 



47 



27 



54 12 



The new form o (014) occurs as a narrow face lying on both 

 sides of the base and four faces of it were observed. The dome 

 n (203) was observed but once as a very narrow face truncating 

 the edge of (223) (223). 



BrocJumtite. — In measuring what were supposed to be eale- 

 donite crystals, it became apparent from the angles that some of 

 the crystals were brochantite. The two minerals are intimately 

 associated, and have the same emerald green color. The crystals 

 are so minute that they had to be handled with a magnifying 



