May 19, 1905.] 



SCIENCE. 



760 



the accidents and disasters which have oc- 

 curred in the Philippine Islands since the 

 American occupation for lack of adequate 

 surveys and charts. It seems eminently 

 desirable that, as fast as the triangulation 

 is sufficiently advanced, a survey should be 

 made of the very extensive shore line of the 

 archipelago by a corps of marine hydrog- 

 raphers. These can determine better than 

 topographers the amount of detail desirable 

 in the line common to land and marine 

 surveys. The line so determined should 

 be accepted by both corps, and from it the 

 hydrographers should work seaward and 

 the topographers inland. The hydrog- 

 raphers will meet with especial difficulties 

 on account of the innumerable coral reefs 

 in the Philippine waters, and may also 

 have trouble with recent uplifts, such as 

 are alleged to have taken place within a 

 few years in the Island of Paragua. There 

 and elsewhere bench-marks should be es- 

 tablished. 



The Coast and Geodetic Survey has al- 

 ready begun work in the Philippines. It 

 has occupied twenty-eight well-distributed 

 astronomical stations, all in telegraphic 

 communication with Manila, commenced a 

 considerable number of harbor surveys, 

 and initiated tidal observations at numer- 

 ous points. It has also planned more ex- 

 tensive operations. 



6. Topof/rap/i?/.— Topographic work in 

 the mountainous and wooded portions of 

 the Philippines will be extremely difficult, 

 the vegetation being so dense as to form an 

 almost complete obstacle to vision and to 

 free locomotion. However, in various por- 

 tions of the archipelago, extensive open 

 plains exist which can be rapidly mapped. 

 It will probably be foimd that the native 

 Filipinos will readily adapt themselves to 

 topographical work, and, as they are ex- 

 traordinarily agile, they will be of great 

 assistance in the mountains and the forests. 

 It is in the highest degree desirable that 



the surveys and si:bdivisions of the public 

 lands should be committed to a topograph- 

 ical corps, such as that of the Geological 

 Survey, as has been done, for example, in 

 the Indian Territory. . The topographical 

 maps should show forest areas, but the dis- 

 crimination of agricultural and mineral 

 lands is not contemplated. As has been 

 already noted, the scales employed should 

 answer to the prospective uses to which 

 the topographical maps are to be applied. 



7. Geology. — The geological problems to 

 be solved are numerous. The economic 

 question of greatest moment is the stratig- 

 raphy of the coal-bearing Eocene forma- 

 tion, which is most extensively developed 

 in southeastern Luzon (Albay and Sorso- 

 gon) and the Island of Cebu. It is prob- 

 able, but not certain, that the coal deposits 

 of Mindanao belong to the same period. 

 The Eocene has been much disturbed and 

 considerably faulted, so that its study will 

 be a somewhat serious task. The coral 

 reefs, volcanoes and earthquakes will neces- 

 sarily also demand the attention of geolo- 

 gists. 



The dense vegetation of the tropics offers 

 great obstacles to the study of geology, and 

 in the Philippines the lack of roads will 

 also delay the work. There is, however, 

 one set of exposures which are admirable 

 and of vast extent, as well as readily ac- 

 cessible by proper means. It has been 

 estimated that there are over eleven thou- 

 sand miles of seaeoast, without counting 

 minor indentations, and along most of this 

 line the rocks are exposed by wave action. 

 The study of the geology of the country 

 will probably proceed most rapidly if be- 

 gun from boats along these coasts, and in 

 beginning geological work on any of the 

 smaller islands it will probably be expedi- 

 ent, as well as most economical, first to cir- 

 cumnavigate the island in steam-launches, 

 mapping the exposures with care. With 

 the information thus obtained it will be 



