128 GEOLOGY. 



is topograpliical and orographical, showing altitudes by means of shades 

 of colour. The mining localities are distinguished by signs. G. A. L. 



Petitot, P. E. Rapport succinct sur la Geologic des vallees de 

 I'Athabaskaw-MackeDzie et do 1' Anderson. [Geology of the Atha- 

 baskaw -Mackenzie and Anderson Valleys.J Pp. 80. Paris. 

 Pinart, Alph. L. Voyages a la Cote Nord- Quest de I'Amerique 

 executes durant les annees 1870-72. Yol. i. part 1. Histoire 

 naturelle. [Travels in Alaska. Natural History.] Pp. 51, 

 5 plates. 4to. Paris. 

 Mineralogy and Geology, by Jannettaz and De Cessac, pp. 13-17. 

 Microscopical Examination and Chemical Analysis of some rocks from 

 Alaska, by J. Leon de Cessac, pp. 19-27. Palaeontology, by A. G-audry 

 and P. Fischer, pp. 29-31. On some fossils from Alaska, by P. Fischer, 

 pp. 33-36. W. AV. 



Powell [Major], J. W. Exploration of the Colorado liiver of the 

 West and its Tributaries, lleport to the Secretary of the Smith- 

 sonian Institution. Pp. 292. 80 illustrations, map, sections. 4to. 

 Washington. [From Notice in Geol. Mag. dec. 2, vol. iii. 

 pp. 365-370.] 

 Describes the canons and their formation : some of them are 600 to 

 1500 feet deep, and but 20 to 30 wide ; and some are more than a mile 

 deep. Also the long lines of precipitous escarpments and the ranges 

 of old volcanoes. The country has a basement of granitic or meta- 

 morphic rocks, with dykes of greenstone and granite. These are suc- 

 ceeded unconformably by 10,000 feet of sandstone, again unconformably 

 overlain by Carboniferous, Triassic ?, Jurassic, Cretaceous, and Tertiary 

 beds. W. W. 



. The Colorado Basin and its Canons. Scribner's Monthly, 



January. 

 Prime, Fred., Jun. On the Occurrence of the Brown Hematite 

 Deposits of the Great Valley. Amer. Journ. ser. 3, vol. ix. 

 pp. 433-440. Amer. Inst. Min. Eng. 

 Gives Analyses of Damourite-slate from 4 places in Lehigh County. 

 These slates are intimately connected with the best ore-deposits in the 

 district; they are of Calciferous age, and not Laurentian or Huronian. 

 The slate lies always below the ore ; and to its impermeability the author 

 attributes to a great extent the richness of the ore. The brown haema- 

 tites were formed probably by the oxidation of iron-pyrites. A trace 

 of sulphur is always to be found in them. G. A. L. 



Raymond, R. W. llemarks on the Occurrence of Anthracite in 

 New Mexico. Trans. Amer. Inst. Min. Eng. vol. ii. pp. 140-143 

 (with discussion). 

 The specimen was from the lignitic formation of Galisteo, 15 miles 

 S. of Santa Fe, which has been classed both as Tertiary and Cretace- 

 ous. The anthracitic character has been given by porphyritic dykes. 

 " It is probable that the eruptive rocks have overflowed, as w^ell as 

 broken through, the coal-bearing sandstones, and hence that a large 



