84: Scientific Intelligence. 



elementary student by giving in certain cases the successive steps 

 of the mathematical discussions in greater detail, so that the 

 whole reasoning can be more easily followed. 



II. Geology and ISTatural History. 



1. United States Geological Survey. — The following portions 

 of the 16th annual report, 1894-95, have appeared*: 



Public Lands and Their Water Supply, by F. H. Newell, Part 

 II, pp. 459-533, pis. 5. Now that the humid public lands have 

 been disposed of, and practically one-third of the total extent of 

 the United States (not including Alaska) semi-humid and arid, is 

 still vacant, it becomes necessary to know its water supply in 

 order to determine the conditions of prosperous development. 

 The report contains a map showing the relative location of forests, 

 woodlands and irrigated areas, and it is gratifying to know that 

 the appropriations for this work, which must furnish the informa- 

 tion for the intelligent administration of public lands, is increas- 

 ing. 



The other papers of Part II of the 16th annual, lately issued 

 and completing Part II, are : — 



Geology of the Cripple Creek Mining District, Colorado, by 

 Whitman Cross and R, A. F. Penrose, pp. 1-209. 



Geology of Road Building Stones of Massachusetts, by N. S. 

 Shaler, pp. 283-328. 



Geology of the Mercur Mining District, Utah, by J. E. Spurr, 

 pp. 344-454 (abstract this Journal, lY, vol. i, p. 395). 



Water Resources of a Portion of the Great Plains, by Robert 

 Hay, pp. 535-588. 



The following Bulletins have appeared recently: 



The Disseminated Lead Ores of Southeastern Missouri, by 

 Arthur Winslow, Bull. 132, pp. 31, pis. 6, 3 colored maps and 

 sections. This report is an explanation of the work published in 

 vols, vi and vii of the present State Geological Survey of Mis- 

 souri. 



Contributions to the Cretaceous Paleontology of the Pacific 

 Coast: The Fauna of the Knoxville Beds, by T. W. Stanton, 

 Bull. 133, p. 132, 20 pis. (abstract this Journal, IV, vol. i, p. 320). 



The Cambrian Rocks of Pennsylvania, by C. D. Walcott, Bull. 

 134, p. 43, pis. 15. This paper records observations made during 

 the summer of 1892 and 1893 upon the belt of Lower Paleozoic 

 rocks and contains a map showing the distribution of the Cam- 

 brian, Silurian and Mesozoic strata in the southeastern portion of 

 Pennsylvania. On page 33 Mr. Walcott says that "The dis- 

 covery of the Olenellus or Lower Cambrian fauna in the Reading 

 sandstone practically completes the correlation of the South 

 Mountain, Chickies, and Reading quartzites, and establishes the 

 correctness of the early correlations of McClure, Eaton, Emmons, 

 and Rogers. They all considered the basal quartzite as the same 



* Six papers in pt. I of the 16th annual are yet to appear. 



