EXPLORATION OF THE CAVES OF BORXEO. 2SB 



combing action of the rain, still present surfaces smoothly polished 

 by the even wash of sea-wave.-;. The exact counterpart of these 

 rocks and of these inland cliffs may be seen in the Philippine 

 Archipelago on the present shores of the islands lying to the 

 northward of Surigao. Such peculiar assemblages of rocks cannot 

 be referred to the action of streams varying their course, for the 

 rocks surround every hill, large and small, and besides, the 

 action of the streams in the limestone district of Sarawak 

 is rather in the direction of cutting one definite channel in 

 the solid rock and keeping to it. Still less could the heavy 

 tropical rains produce such results by their long-continued opera- 

 tion over a rock-surface of unequal hardness. Were there no 

 other argument against such a supposition, the presence of the 

 "mushroom " rocks would be fatal to it. 



Pa£e278. — " Sarawak Coast advancing seaward." — The 



shore line of north-west Borneo (Sarawak) appears to be gaining 

 on the sea steadil} r as a whole. Whether the land is stationary 

 and the gain is clue solely to the amount of sediment poured into 

 the sea by an extensive river system, draining a country composed 

 of rocks peculiarly liable to rapid degradation by denudational 

 agencies and exposed, at the same time, to a rainfall equalled by 

 that of few countries on the face of the globe, or whether, in 

 addition to the shoaling of the sea by the introduction of fluviatile 

 debris, the land is at present undergoing a slow elevatory movement, 

 I do not feel prepared to decide. Of the mere fact of the recent in- 

 crease of the land there is abundant evidence. The coast between 

 Lundu and Samarahan, and again, between Kalakah and Igan, is a 

 flat belt of alluvial soil, but just raised above the level of the highest 

 tides, and traversed in every direction by broad tidal channels. The 

 belt extends inland from ten to thirty miles. Cape Sirik is its 

 most prominent point, and, although it is composed of soft allu- 

 vium, and is exposed to the fury of the north-east monsoon, blow- 

 ing clown the whole expanse of the China Sea, this cape extends 

 itself so rapidly seawards that the subject is one of common re- 

 mark among the natives in its vicinity. The Paloh Malanaus have 

 farmed close up to the point for many years past, and they state 

 the addition to the land annually to average three fathoms. One 

 of the elder men pointed out a distance of nearly two miles, as 



