Transcriber's Note:
A number of obvious typographical errors have been corrected in this text.
For a complete list, please see the bottom of this document.
Introduction.—The occasion for publishing this catalogue ofPhilippine earthquakes which were of violent and destructive characterhas been furnished by a request from Prof. John Milne for a list ofsuch phenomena, to be included in the General Earthquake Cataloguewhich this eminent seismologist is preparing under the auspices of theBritish Association for the Advancement of Science. The said generalcatalogue has been undertaken with a view toward reducing touniformity and completing those published years ago by Robert Mallet(1859) and Perrey (1844-1871). The form adopted for Professor Milne'snew catalogue is very concise, comprising only the date, intensity,and region together with principal localities affected. It willcontain only the earthquakes of intensities VII to X according to thescale of De Rossi-Forel, and these will be divided into three classes:Class I will be formed by the earthquakes of sufficient force toproduce cracks in buildings and to throw down chimneys; theycorrespond to force VII of De Rossi-Forel. Class II consists of theearthquakes which not only threw down chimneys but also walls and someweak structures; force VIII of De Rossi-Forel. Class III comprises theearthquakes which caused general destruction; force IX and X of DeRossi-Forel. As this classification is as purely conventional as everyother and adopted only in the catalogue mentioned, we do not employ itin the present catalogue of Philippine earthquakes, but retain thealmost universally adopted scale of De Rossi-Forel. We shall alsopresent more details as to the towns and buildings damaged, the numberof victims and other disastrous effects than enter into the catalogueof Professor Milne.
Hence, the differences between the list prepared for Professor Milneas well as the partial catalogue published in our Monthly Bulletin forFebruary of the present year consist in the following: (1) Thiscatalogue contains also several earthquakes whose intensities werebetween VI and VII, while in the former only such figure as accordingto their effects were decidedly of force VII. (2) The new catalogue ismore complete as to details concerning the towns, etc., which havebeen destroyed.
It is to be regretted that we are unable to present here a completehistorical catalogue of all the destruction wrought in the Archipelagoby earthquakes since the time when Legaspi and Urdaneta first set footon these shores. But the old chroniclers, who dwell upon the politicalhappenings with an attention to detail which is occasionally overdone,were invariably laconic when there was question of earthquakes andsimilar natural phenomena; as a rule they