Catalogue of Violent and Destructive Earthquakes in the Philippines | Page 3

to designate the
months. Unfortunately, of some earthquakes only the year is known; of
others, the year and month. Of one (No. 32) the approximate hour has
been recorded, but not the day of the month; while of another (No. 38)
the hour has been preserved for posterity, but whether the phenomenon
occurred during February or March, the records leave undecided. In the
third column will be found, in the first place, the intensity of the
disturbance, Roman numerals representing the degrees of the scale of
De Rossi-Forel (I-X); then the region affected most, and finally the
damages caused, if known, and other information, if available.
In describing the epicentral regions, the present distribution of the
Archipelago into provinces has been used throughout the catalogue.
This division is shown on the first of the two maps of the Philippines
which accompany this catalogue (Plate I). As to the designation
"Benguet" occasionally occurring in the text where provinces are
enumerated, but not found on the map, we beg to offer the excuse that
the region thus named is exceedingly well known in the Philippines as
it contains Baguio, the health resort of the Islands. For the readers
outside of the Archipelago we remark that Benguet is at present a
subprovince of the Mountain Province, of which it forms the
southernmost part. The location of Baguio is shown on the map on

Plate II. A similar remark applies to Lepanto and Bontoc, likewise
divisions of the Mountain Province, whose capitals, Cervantes and
Bontoc, are indicated on the same map.
As we would hardly be justified in assuming that every reader is in
possession of a detailed map of the Philippines, and a knowledge of the
general distribution and the main directions of the principal mountain
systems of an earthquake country is important, we add a second map on
which these data are shown by means of dashes, together with the most
important seismic regions, and the positions of the principal towns,
bays, etc., mentioned in the text. (Plate II.)
Near the left margin of this second map will be found an index of the
seismic regions just mentioned, each of them being represented by its
ordinal number (large Roman figures). Near each of these ordinals is
placed the corresponding number of earthquakes since 1862 contained
in the catalogue (Arabic figures), which is followed, in brackets, by an
analysis of the said number, in which Roman figures designate the
degrees of the earthquake, scale of De Rossi-Forel, while small Arabic
figures, written like exponents, give the number of earthquakes of each
degree of intensity.
In drawing the map on Plate II it was not intended to represent the
epicentric area of every individual earthquake center (which would
have crowded the map beyond reasonable limits), but rather to show
the principal seismic regions. Hence most of these curves contain more
than one focus. The approximate position of each of the latter has,
however, been indicated by a star, while the figure placed close to the
star gives the number of earthquakes which proceeded from the said
center.
A word must be said in apology for the constant use in the following
list of the Spanish word "convento." This word which means monastery,
cloister, or convent, is universally used in the Philippines to designate
also the habitation of the clergy attached to a parish church. Although
these are, as a rule, spacious buildings and were formerly inhabited
well-nigh exclusively by friars, they can not properly be called
monasteries. Wherefore, in order to avoid lengthy circumlocutions, the

Spanish word "convento" has been retained.
The reader who is not familiar with this country may find it strange that
in reporting earthquake damages so much emphasis appears to be laid
on the harm done to churches and conventos. This is easily explained
by the fact that these buildings were often the only structures within the
meizoseismal area, and built nearly everywhere in the most substantial
manner.
In the present catalogue we have also included, by way of an appendix,
the earthquakes which are known to have occurred in the Marianas or
Ladrones group of islands. While their number is too small to warrant
separate publication, we believe that the data concerning them will be
welcome to the earthquake investigator.

CATALOGUE OF VIOLENT AND DESTRUCTIVE
EARTHQUAKES IN THE PHILIPPINES.
----+--------------------+-----+------------------------------------------ No. |
Date. |Intensity. | | | Epicenter and effects.
----+--------------------+-----+------------------------------------------ | Y. M.
d. h. m. | | 1 |1599 VI 25 3 20 | IX |Manila and neighboring provinces.
Damaged | | |many private buildings in Manila; cracked | | |the vault of
the Jesuit Church so badly | | |that it had to be demolished and replaced |
| |by a ceiling; fissured the walls and | | |ruined the roof of Santo
Domingo Church. | |