Reviews — The San Francisco Earthquake. 319 



K E ^V I E 'W S- 



I. — The San Francisco Earthquakk. 

 Thk California Earthquake of April 18, 1906: Report of the State 

 Earthquake Investigation Committee. By Andrew C. Lawson, 

 in collaboration with G. K. Gilbert, H. F. Reid, and others. 

 Carnegie Institution of Washington. 

 ^IIHREE days after the earthquake which destroyed so large a part 

 \_ of San Francisco in 1906, a committee was appointed by the 

 Governor of California for the purpose of investigating the different 

 phenomena, both transitory and permanent. The committee included 

 Professor A. C. Lawson as chairman and several well-known men of 

 science. Working in conjunction with them were also many other 

 observers, who investigated various details and examined the whole of 

 the ground traversed by the great fault, and pliotographed and measured 

 the displacements of tlie surface-beds. By the end of the year the 

 materials were nearly all collected, and the residts of the discussion 

 when completed will fill two quarto volumes and a folio of maps and 

 plates. Of these the first volume and the atlas are already published. 

 The former contains the record of the facts observed, the detailed 

 account of the fault and of the movements along it whicli caused the 

 earthquake, the description of the secondary phenomena and of the 

 variations of intensity throughout the disturbed area. The second 

 volume will be occupied by an investigation of the seismographic 

 records of the earthquake obtained at observatories in all parts of the 

 world. The theory of the seismograph will also be considered in some 

 detail. In the atlas the course of the fault is clearly traced, the 

 variations of intensity in the shock are depicted, especially within the 

 city of San Francisco, and the seismograms from nearly seventy 

 observatories are reproduced. In addition to the forty plates in the 

 atlas there are more than three times that number in the first volume, 

 chiefly reproductions of photographs. The report is published by the 

 Carnegie Institution of Washington, and it is evident that no expense 

 and no trouble on their part have been spared to make it the most 

 complete account ever furnished of any scientific phenomenon. Nor 

 have Professor Lawson and his colleagues failed in any way to take 

 advantage of so unique an opportunity. Their work has been admirably 

 done. The immense mass of detail is carefully collated. Whenever 

 possible the editor has allowed the observers to speak for themselves 

 in short notes and papers, which are so neatly inserted that in reading 

 the text there seems to be no breach of continuity. 



The advantages of this mode of collaboration are nowhere better 

 illustrated than in the description of the remarkable fault which 

 occupies so large a part of the first volume. The fault was traced by 

 diiferent observers for a distance of at least 190 miles, except for a few 

 short interruptions in which its course is submarine, and there can be 

 little doubt that it reappears after a somewhat longer break still 

 farther to the north, so that the total length of the line is about 270 

 miles. On the whole, the path of the fault is a slightly curved line 

 running in a general north-west and south-east direction, and, to the 

 north of San Francisco, keeping close to the Californian coast. Its 



