490 SMITH. 



some 300 meters higher. In the middle distance stands a prominent, 

 grass-covered bump known as "Signal Hill" and beyond lies the lake and 

 still farther back the dark, volcanic range of the Butig Mountains on 

 the southeast. To the southwest the striking peaks known locally as 

 "Ganasi" appear. 



Usually, when the visitor first sees Lake Lanao, if he has any curiosity 

 at all, he seeks the most natural explanation in a volcanic region, namely, 

 that it is a crater lake. There may be some resemblance to a crater rim 

 on the south shore near Camp Vicars, but in other places there is no 

 trace of it. I first was favorably inclined to the belief that it was a 

 valley dammed by glacial wash and I found no trouble in likening the 

 Keithley Escarpment to a terminal moraine. I was forced to abandon 

 this hypothesis for reasons which will be stated in. a paper on the geology 

 of this region which is to follow. My provisional conclusion with regard 

 to Lake Lanao is that it occupies an old basin, partly tectonic, partly 

 caused by erosion, between the mountains; this basin has been dammed 

 by lava flows and other volcanic materials from the mountains adjacent 

 to it. Subsequent weathering has given the aspect of a pseudo-glacial 

 till to the material forming this obstruction. The explosion-crater theory 

 has occurred to me and some attention will be paid to it in this con- 

 nection- in the later geologic discussion. 



Camp Keithley is situated partly on the brow of the escarpment of 

 the same name and partly on the slope to the lake. The small village of 

 Marahui lies on the. lake shore on the west bank of the Agus. Here is 

 the residence of the district governor and here too, the tribal court is 

 held. This village also has a native market, so that Marahui is the best 

 place in the whole lake region to see the Moro people. 



Mr. Ickis joined the party in Marahui and we crossed Lake Lanao 

 in a vinta with a large sail and awning made of some species of palm. 

 It was almost nightfall when we ran into a small cove and landed, and 

 in the darkness we began the ascent of 155 meters up the high bluff on 

 which Camp Vicars is situated. This distance is between 4 and 5 kilo- 

 meters. Three days later we set out for the Taraca River on the east 

 side of the lake with an escort of twenty scouts, sixteen cargadores, 

 and several guides. The country around Vicars is open and rolling and 

 very similar to that south of Lake Lanao. Very little of the land is 

 under cultivation. 



On the second day we finally descended from the high bluff we had 

 been following and crossed an estuary, thus saving many miles of cir- 

 cuitous travel. The low flat.s wliich border this side of the lake extend 

 back for several miles. The trail on the other side of this estuary 

 lies through paddies and swampy areas. Every morning during our 

 march was clear and bright, but the afternoons without an exception 

 were rainy. 



