82 Scientific Intelligence. 



air to water and forest, the heat movement in the ground, 

 and observations above the earth by means of balloons and other 

 methods ; the discussion of the phenomena of atmospheric elec- 

 tricity has been rewritten. 



10. Refraktionstafeln / von Dr. L. de Ball, Direktor der v. 

 Kuffnerschen Sternwarte. Pp. xiv, with 1 1 tables. Leipzig, 

 1906 (Wilhelm Engelmann). — The tables here included are based 

 upon Radau's theory of refraction ; the refraction constant 

 assumed is that of Bauschinger, namely, 60"*15 for normal con- 

 ditions of pressure in temperature and at sea-level at a latitude 

 of 45°. There are eleven series of tables, and the special mathe- 

 matical sources upon which they are based are explained in the 

 Introduction, which is printed both in German and French. 



1 1 . Shaft Governors ; by W. Trinks and C. Housum. Pp. 

 11, 97, with 27 figures and 16 tables. Van Nostrand Science 

 Series, No. 122. New York, 1905 (D. Van Nostrand Co.).— This 

 recent addition to the Van Nostrand Science Series will be prop- 

 erly valued by those who have to do with the use of shaft 

 governors in practical machinery. 



II. Geology and Mineralogy. 



1. Preliminary Report of the State Earthquake Investigation 

 Commission; 17 pp. Berkeley, May 31. — The Governor of Cali- 

 fornia, on April 21, 1906, appointed a commission to examine and 

 report on the phenomena connected with the earthquake which 

 occurred three days previously at San Francisco. The members 

 of the Commission are as follows: A. C. Lawson, of the Univer- 

 sity of California ; G. K. Gilbert, of the U. S. Geological Survey; 

 H. Fielding Reid, of Johns Hopkins University ; J. C. Branner, 

 of Stanford University; A. O. Leuschner and George Davidson, 

 of the University of California ; Charles Burkh alter, of the Chabot 

 Observatory, and William Wallace Campbell, Director of the 

 Lick Observatory. 



In the preliminary report it is stated that the plane of disloca- 

 tion was along the well-known fault-line which extends in a 

 remarkably straight line obliquely across the Coast Range from 

 Point Arena to Mount Pinos in Ventura County, a distance of 

 375 miles. This physiographic line " affords every evidence of 

 having been in past time a rift, or line of dislocation, of the 

 earth's crust and of recurrent differential movement along the 

 plane of rupture. The movements which have taken place along 

 this line extend far back into the Quaternary period, as indi- 

 cated by the major, well-degraded fault scarps and their asso- 

 ciated valleys; but they have also occurred in quite recent times, 

 as is indicated by the minor and still undegraded scarps. Prob- 

 ably every movement on this line produced an earthquake, the 

 severity of which was proportionate to the amount of movement." 



"The earthquake of the 18th of April, 1906, was due to one of 

 these movements. The extent of the rift upon which the move- 



