abstracts: geology 161 



to 40°C. Tables 2 to 8, inclusive, are standard density and specific grav- 

 ity tables for ethyl alcohol. They are based on work done at this Bureau 

 and published in Vol. 9, No. 3, of the Bulletin of the Bureau of Stand- 

 ards (Reprint No. 197). Tables 9 to 11, are similar tables for methyl 

 alcohol. They are based on the work of Doroshevskii and Rozhdest- 

 venskii. Tables 12 and 13 are density tables for sugar solutions. 

 Tables 14 and 15 are density tables for sulphuric acid solutions. Tables 

 16 to 19 give the relation between specific gravity and degrees Baum^, 

 in use in the United States. Table 20 is for changing the density basis 

 of hydrometers and picnometers. Table 21 gives the weight of a liter 

 of air at various pressures and temperatures. Table 22 gives the 

 difference between the weight of 1 cc. of water in vacuo and in air at 

 various pressures and temperatures. Table 23 gives the apparent weight 

 of various volumes of water at various temperatures when weighed 

 against brass weights in air. Table 24 gives the temperature correction 

 for glass volumetric apparatus. Tables 25 to 37 give the corrections 

 to be applied to the weight of water, in air, to give the capacity of glass 

 volumetric apparatus. Table 38 gives the density of water (according 

 to Thiesen) at temperatures from 0° to 102°C. Tables 39 and 40 are 

 master scales for the graduation of hydrometers to indicate percentages 

 of ethyl alcohol by weight and by volume and percentages of "Proof 

 Spirit." G. K. B. 



GEOLOGY. — The Noatak-Kobuk region, Alaska. Philip S. Smith. 

 U. S. Geological Survey Bulletin 536. Pp. 160, with maps and 

 illustrations. 1913. 

 Practically all of the Noatak-Kobuk region lies north of the Arctic 

 Circle, and as a whole is a mountainous region. The rocks from which 

 the geology of the region has been inferred have been separated into 

 two main divisions, namely, sedimentary and igneous. The sedimen- 

 tary rocks have been divided into thirteen groups as follows: Unconsoli- 

 dated deposits consisting of recent stream gravels; recent beach deposits; 

 beach and outwash deposits; Tertiary deposits; the Mesozoic rocks 

 separated into the Bergman, Koyukuk, and Anaktuvuk groups; the 

 Paleozoic rocks subdivided into the Lisburne limestone, Noatak sand- 

 stone, Devonian limestone, Silurian limestone, undifferentiated Paleo- 

 zoic limestones, and undifferentiated Paleozoic metamorphic schists. 

 The last two divisions of Paleozoic rocks may possibly include some 

 rocks of pre-Paleozoic age. The igneous rocks have been subdivided 



