VULCANOLOGY AND SEISMOLOGY. 479 



and Segovia, toward the west by C^ceres and Huelva, toward the east 

 by Valencia and Murcia, and on the south by the Mediterranean; but 

 the tremor of the earth was also indicated by instruments even so far 

 distant as Home and Brussels and Wilhelmshaven. {Nature, xxxi: 491.) 

 Examination of the direction of the cracks in the ground and in build- 

 ings, as well as of the curves of intensity estimated accoriiing to the 

 Rossi-Forel scale, leads to the conclusion that the focus is to be found 

 in the valley of Zaffaraya, where the greatest damage was caused. The 

 latter halt of the report is occupied with the physical, magnetic, barom- 

 etric, and other jih^nomena attending the earthquake. The number of 

 bnildings injured in the two i)rovinces is stated at 17,178, of which 4,399 

 are classed as totally destroyed. The injured persons numbered 745 

 dead, and 1,485 wounded. In discussing the cause of this earthquake 

 the commission accepts the Italian theories, attributing earthquakes to 

 the tension of the vapor of water in the subjacent strata. The valley 

 of Zaffaraya, indicated above as the probable focus, is a locality where 

 much water gathers and easily penetrates beneath the surface, and to 

 the vapor of high tension produced from the water here collected in 

 deep lying strata are attributed the forces which gave rise to the present 

 earthquake. The commission consisted of M. F. de Castro, J. P. Lasala, 

 Daniel de Cort^zar, and J. Gonzalo y Tarin. 



On March 2, M. Fouqu^ gave to the French Academy a preliminary 

 report on the exploration which the committee under his charge had 

 made of the phenomena of the Spanish earthquakes. The committee 

 consisted of MM. Fouqu6, L6vy, Bertrand, Barrois, Offret, Kilian, 

 and Bergeron, and was accompanied by M. Breon. This first commu- 

 nication speaks only of their journey, the facilities afforded by the Span- 

 ish authorities, aud certain phenomena observed, reserving the discus- 

 sion of theoretical questions to another time. {Compt. Eend.^G: 598.) 



The full reports of the French committee may be found in Comptes 

 Rendus Tome c, and besides a general consideration of the phenomena 

 and their cause, they include two special reports on the geology of the 

 district by members detailed for that purpose. In the general con- 

 clusions reached they agree with the Spanish commission, and fix the 

 centrum in an elliptical area surrounding Zaffaraya ; but in regard to 

 the cause of the disturbance M. Fouque rejects the theory which at- 

 tributes it to the local tension of water vapor, and would refer it rather 

 to the general volcanic forces within the globe. 



The Meteor ologuche Zeitschrift for February, 1885, contained a notice 

 by Dr. Eschenhagen on the effect which was apparently produced by 

 the Andalusian earthquakes on the magnetic apparatus at Wilhelms- 

 haven. The effect seems to have been not at all of a magnetic charac- 

 ter, but ])urely mechanical, the delicately suspended magnets acting as 

 the ]>endulum of a seismoscope. Attempts to draw from the observed 

 times sDme inference as to the rate of propagation of tiie disturbance 



