Introduction.--The occasion for publishing this catalogue of
Philippine earthquakes which were of violent and destructive character
has been furnished by a request from Prof. John Milne for a list of
such phenomena, to be included in the General Earthquake Catalogue
which this eminent seismologist is preparing under the auspices of the
British Association for the Advancement of Science. The said general
catalogue has been undertaken with a view toward reducing to
uniformity and completing those published years ago by Robert Mallet
(1859) and Perrey (1844-1871). The form adopted for Professor Milne's
new catalogue is very concise, comprising only the date, intensity,
and region together with principal localities affected. It will
contain only the earthquakes of intensities VII to X according to the
scale of De Rossi-Forel, and these will be divided into three classes:
Class I will be formed by the earthquakes of sufficient force to
produce cracks in buildings and to throw down chimneys; they
correspond to force VII of De Rossi-Forel. Class II consists of the
earthquakes which not only threw down chimneys but also walls and some
weak structures; force VIII of De Rossi-Forel. Class III comprises the
earthquakes which caused general destruction; force IX and X of De
Rossi-Forel. As this classification is as purely conventional as every
other and adopted only in the catalogue mentioned, we do not employ it
in the present catalogue of Philippine earthquakes, but retain the
almost universally adopted scale of De Rossi-Forel. We shall also
present more details as to the towns and buildings damaged, the number
of victims and other disastrous effects than enter into the catalogue
of Professor Milne.

Hence, the differences between the list prepared for Professor Milne
as well as the partial catalogue published in our Monthly Bulletin for
February of the present year consist in the following: (1) This