K W. Morley — Moisture in Gas. 199 



Page. 

 Figure 12. — Protospongia, sp. undet. 



12, characteristic spicula.. 



Figure 13. — Leperditia (I) dermatoides, n. sp 192 



13, left (?) valve and outlines of its convexity ; 13a, enlargement to show 

 punctate surface and the wrinkled appearance of the test, as seen on 

 some specimens. 



Figure 14. — Kutorgina pannula "White, (sp.) 190 



14, dorsal valve; 14a, enlargement of surface of 14; 146, enlargement of 

 surface of a specimen from Pioche, Nevada, for comparison and also to 

 correct the figure on pi. viii, Bull. 30, (J. S. Geol. Survey. 



Figure 15. — Lingulella Granvillensis, n. sp 188 



15, dorsal valve preserving portions of the outer shell; 15a, cast of the in- 

 terior of a dorsal valve, showing muscular scars and vascular markings ; 

 156, 15c, ventral valves, showing elongate muscular scars and fragments 

 of the outer shell. 



Figure 1 6. — Lingulella ccelata Hall, (sp.) 



16, cast of the interior of a dorsal valve. (See Bull. 30, U. S. Geol. Survey.) 



Figure 17. — Orthis Salemensis, n. sp 190 



17, ventral valve and outline of its convexity; 17a, dorsal valve. 



Figure 18. — Linnarssonia Taconica, n. sp 189 



18, ventral valve; 18a, interior of ventral valve: 186, cast of the interior 

 of a ventral valve ; 18c, dorsal valve ; 18c?, cast of the interior of a dor- 

 sal valve. 



Figure 19. — Modiolopsis ? ? prisca, n. sp._ 191 



19, cast of right (?) valve very much elongated. The outline of the con- 

 vexity of the valve is shown by lines beside the figure. 



Art. XXIII. — On the amount of Moisture remaining in a Gas 

 after drying by Phosphorus Pentoxide ; by Edward W. 

 Morley. 



I have now determined the amount of aqueous vapor left 

 in a gas after drying it with phosphorus pentoxide, by the 

 method applied in the case of sulphuric acid.* The process 

 consists in drying the gas with phosphorus pentoxide, and 

 then passing it through a weighed apparatus in which the gas 

 is first slightly moistened, then much expanded, and lastly 

 again dried by phosphorus pentoxide. If the weight of the 

 apparatus decreases, the loss is due to the moisture left by 

 phosphorus pentoxide in that volume by which the gas passing 

 out of the apparatus exceeds the gas entering it. 



If it were required in this matter to determine with some 

 precision a physical constant, numerous experiments would be 

 needed, and the results of the experiments now completed, 

 show that each experiment would have to be continued for 

 some years. But for settling a practical question concerning 

 chemical manipulation, the two experiments now completed 



* This Journal, vol. xxx, p. 141. 



