NATALITE. 373 



in the sulphurets fsparingly disseminated tlironglioiit the rock specimen. It 

 is associated witli pyrite and millerite in vesicuhir (juartz. Tlie specific 

 Ufravity is 1 .0:^. 



Tlie following analyses were made on tln-ee different samples : (I) Pure 

 material selected from that in the rock specimen ; (II) material dissolved in 

 ether filtered, and the filtrate allowed to solidify spontaneously; (III) ma- 

 terial fused at a low temperature and allowed to How away from small frag- 

 ments of rock : 



I Hydrogen, H 10. IT 



10.36 1 10.11 



99. 90 99. 46 



The resin is therefore a hydrocarbon, and the analyses correspond 

 closely to the formula VHV, which would contain tlO i)er cent, of carbon. 

 Since it is decomposed by heat its vapor density cannot be determined, and 

 its structural fornuda cotdd not be ascertained Avithout a more elaborate 

 investigation than was practicable. This mineral has not been described, 

 and must therefore be named. The term uapuUte seems unobjectionable. 



()u the loO and 300 foot levels inflammable gas issues from cracks. As 

 shown by the following analyses by Dr. Melville, the chief component is 

 marsh gas : 



Cixrbouic auliyilridc 0. 74 



Marsli gas ''I- ^'^ 



Nitrogen •- 31.44 



Oxygen 0.33 



100. 00 



The Starr deposit, belonging to the same company, is said to have 

 produced five thousand flasks of quicksilver and is of peculiar geological 

 interest. It occurs at the contact between a basalt dike and the sandstone 

 through which the lava has broken. The ore occurs both in the sandstone 

 and in the basalt along the contact. The workings extend to a deptli of 

 400 feet from the surface and the ore is not yet exhausted. 



Similar to the last and also on the property of the ^Etna Company is 

 the Silver Bow. So far as observed, the ore in this mine is wholly in the 



