Report of the governor general of the Philippine Islands. [1908]

546 REPORT OF THE PHILIPPINE COMMISSION.
soundings and tidal observations. This work was completed on the 25th, and
on the following day she sailed for Mercedes, where she arrived on the 27th; the
next day coaled ship and located three new buoys recently placed in the mouth
of the Daet River. On the 29th she proceeded to Capalonga and erected an
automatic tide gauge in the estuary of that river and on the following day
sailed for Atimonan, where the triangulation was taken up to connect the
main scheme, which was brought across the divide from the west side of Luzon,
with the triangulation of Lamon Bay and again with the triangulation of
Calaguas Islands. Almost continuous cloudy and rainy weather interfered
with the use of heliotropes, which were required on all the lines, and a great
deal of steaming was demanded of the ship to keep all parties moving, but
the connection was completed before the end of June and we now have a continuous scheme of triangulation from the north coast of Luzon to the southern
extremity of Samar.
The tidal observations show a gratifying improvement in quality since a
regular tidal observer has been employed. Heretofore it had been the custom
to detail one of the seamen of the vessel for that purpose, and the results were
far from satisfactory.
STEAMER " MARINDUQUE."
Was in Manila repairing and outfitting from July 1 to 9, and on the 10th
Sailed for the east coast of Luzon, where she arrived on the 14th, and took up
General surveys of Lamon Bay and vicinity in continuation of the work of the
previous year.
The triangulation was taken up in the vicinity of Alabat and Atimonan and
carried around the southern end of Lamon Bay and out Calauag Bay to Pangao
Point.
The topography was completed around the shore of Luzon from Atimonan to
1)agdap, also along the shore of Alabat Island from Muel around the south end
of the island and up the eastern shore to Gerado Point, where it connected
with the work of the preceding year. She also made a survey of Balesin Island.
The hydrography included the south end of Lamon Bay, Calauag Bay, and
was extended out to Dagdap Point, Balesin and Cabaleto islands.
The season was closed on October 13 and the vessel sailed for Manila, where
she arrived on the 15th and was engaged repairing and outfitting until the 22nd,
when she sailed for Palompon, Leyte, where she arrived on the 24th, and on the
following day resumed the general surveys between Cebu and Leyte and extended it northward from the previous work in that vicinity.
The triangulation was started from the line " Bulalaqui" to "Malcamko"
and carried around the northern extremity of Cebu Island and into the northern entrance of Tanon Strait, ending on the line " Escalante" to " Putad" and
also around the north end of Leyte Island and through Biliran Strait into Carigara Bay.
The topography was completed along the east coast of Cebu from Bantulin to
Campatoc Point, along the west coast of Leyte from Villaba around Rabin
Point, through Biliran Strait into Carigara Bay, and also around the south and
west shore of Biliran Island from Matuntun Point to Tincansan Island.
The hydrography included the area between Cebu and Leyte, from Bantulin
and Duljugan points on the south to the northwest end of Biliran Island and
through Biliran Strait into Carigara Bay.
Field work was closed in this vicinity on April 2, and the vessel arrived in
Manila on the 4th, where she remained for repairs, outfitting and compiling
their records and reports until May 18, when she sailed for the eastern coast of
Luzon, arriving at Atimonan on the 22d. Field work was immediately commenced, but stormy weather prevailed during the remainder of the month, and
the completion of one topographic sheet and some signal building was all that
could be accomplished. The month of June, however, was much more favorable
for field work and the triangulation between Polillo and Luzon, four topographic sheets having been completed.
Numerous difficulties were encountered in advancing the triangulation. At
some of the stations four or five days' clearing was required. Four scaffold signals had to be erected and this consumed considerable time, the heights of these
scaffolds being 30, 40, and 150 feet, approximately. Whenever possible a large
tree 4 or 5 feet in diameter at the base was selected as a center, these trees
being often over 150 feet high and very straight, with few branches. They
were sawed off as high up as possible and the theodolite mounted on top.
Around the tree, and entirely free from it, a quadrilateral scaffold was built
for the observer to walk on, so as not to jar the instrument. The triangle clos