T 



HE following communication was read :- 



On the Igneous and Associated Sedimentary Eocks of the 

 Tourmakeady District (County Mayo).' By Charles Irving Gardiner, 

 M.A., F.G.S., and Prof. Sidney Hugh Reynolds, M.A., F.G.S. With 

 a Paheontological Appendix by Frederick Richard Cowper Reed, 

 M.A., F.G.S. 



January 13th, 1909.— Prof. W. J. Sollas, LL.D., Sc.D., F.R.S., 

 President, in the Chair. 



The following communications were read : — 



1. 'On Labradorite-Norite with Porphyritic Labradorite.' By 

 Prof. Johan H. L. Vogt, F.M.G.S. 



This paper deals with a rock occurring at Napp Farm, on 

 Flakstado, off the northern coast of Norway. It contains 23 per 



Phil. Mag. S. 6. Vol. 17. No. 101. May 1909. 3 F 



Geological Society. 769 



Department of Commerce and Labor, Coast and Geodetic Survey. 

 O. H. Tittmatstn, Superintendent. United States Magnetic 

 Tables and Magnetic Charts for 1905. By L. A. Bauer, In- 

 spector of Magnetic Work and Chief of Division of Terrestrial 

 Magnetism. Washington : 1908. Pp. 151. Large octavo, 

 with 7 charts. i i 



The volume consists mainly of tables, comprising observed values 

 of the magnetic elements and the values thence deduced for the 

 epoch January 1, 1905. Data are given for over 4000 land 

 stations — including fully 800 outside the borders of the United 

 States itself — and for more than 200 stations at sea. There are 

 also voluminous tables showing the secular change in the elements 

 throughout the United States, going back in a good many cases to 

 1750. The results are embodied in 7 charts. The first 5 show 

 the isogonals, isoclinals, and isomagnetics (of horizontal, vertical, 

 and total intensity). The sixth shows the curves that would be 

 traced on the earth's surface by one always travelling in the 

 direction in which the compass -needle points. The last chart 

 contains two types of curves, illustrating the secular change in the 

 elements. Though the epoch selected is January 1, 1905, use is 

 made of observational data as recent as midsummer 1907. The 

 charts are of large size and aim at showing all local irregularities 

 of importance. 



LXXIV. Proceedings of Learned Societies. 



GEOLOGICAL SOCIETY. 1 1 



[Continued from p. 332.] 



December 16th, 1908.— Prof. W. J. Sollas, LL.D., Sc.D., F.R.S., 

 President, in the Chair. 



