Geology and Natural History. 489 



Volume iii, part I, was begun by the state geologist, whose 

 health broke down after completing the earlier chapters ; the 

 remainder of the work was prepared by Messrs. E. V. d'Invilliers 

 and A. D. W. Smith. This part includes the discussion of the 

 Carboniferous in general. In the second part of vol. iii, the bitu- 

 minous coal fields are described by M. d'Invilliers, and the New 

 Red of Bucks and Montgomery counties is described by Benja- 

 min Smith Lyman. For the purposes for which these volumes 

 were designed they seem to be admirably adapted, and for scien- 

 tific students of geology they constitute a very convenient sum- 

 mary of the immense amount of detail of Paleozoic geology 

 developed by the corps of the Second Pennsylvania Geological 

 Survey. Mr. Ingham, the secretary of the Board of Commission- 

 ers, has added under separate covers a general index with an 

 appendix containing a list of, and brief guide to, the publications 

 of the survey. h. s. w. 



4. The Geology of the Road- Building Stones of Massachu- 

 setts, with some Consideration of Similar Material from other 

 parts of the United States ; byN. S. Shaler ; (extract from 16th 

 Ann. Report U. S. Geol. Survey 1894-95, Part II, pp. 277-341.) — 

 Following the more general treatment of the geology of common 

 roads of the United States, which appeared in the 15th Annual 

 Report, Professor Shaler has here given, in his customary clear, 

 terse and vivid manner, a practical account of the nature, mode 

 of occurrence and values for road-making of the rocks found on 

 the surface of Massachusetts. In the section upon tests the author 

 emphasizes the considerable importance of the cementing quality 

 of the fine material produced by the wear of the stone ; remark- 

 ing that the experiments " indicate that it may be desirable in 

 certain cases, when a stone otherwise suitable for macadam pur- 

 poses does not afford from its powder a good cement, to cover 

 the road with dust made by grinding some other variety of stone 

 which will form a firmer bond." He speaks of the saving of 

 expense in the use of properly selected glacially-distributed 

 bowlders over quarry stone, and estimates that an average of 35 

 cents per ton may be thus saved in the construction of roads in 

 the State of Massachusetts, amounting in the aggregate to seven 

 million dollars in twenty years. In the Connecticut valley region 

 the finest of all road-metal is found in the " trap " rock of the 

 dikes. The materials available for road-making are discussed 

 primarily under three divisions : i.e., drift-materials, bedded rock 

 and dike and vein stones, and under each of these heads the dis- 

 tribution within the state is noted. 



A table of statistics closes the report, concerning the resistance 

 to wear of road-building stones based upon tests made by Mr. L. 

 W. Page, Geologist of the Massachusetts Highway Commission. 



h. s. w. 



5. The University Geological Survey of Kansas, conducted 

 under authority of the Board of Regents of the University of 



Kansas; by Erasmus Haworth and assistants. Yol. 1, pp. 



