LUZON. 543 
many yards in diameter. There is a broad plain at top lying between 
two prominent points. The hill consists of tufa, and appears to re- 
semble “ Punchbowl” Hill on Oahu; the layers dip at an angle of 
thirty or thirty-five degrees, and are from a few inches to five feet in 
thickness. The tufa is a soft friable rock, scarcely at all indurated, 
consisting of coarse and fine fragments of scoria and pumice imbedded 
in finer volcanic ashes. 
The Hot Springs at Banos have been frequently mentioned by travel- 
lers. ‘There are about a dozen springs, three of which pour out copious 
streams of water. A stone aqueduct has been built up around the main 
one ; the water rushes out with considerable force, and spreading itself 
over the shores, flows into the lake. The temperature of the water 
where it leaves the aqueduct is 178° F. Over two steaming pools, domes 
had been built, about six feet in diameter, for use as steam bathing 
houses; the temperature of one was 160° F., and that of the other 
140° F’.: the latter, I was told, had of late diminished in temperature. 
About another place near the aqueduct there was a stone wall, enclos- 
ing stone reservoirs for baths. ‘The place was once a fashionable re- 
sort for the gentry of Manilla; but everything is now in decay. The 
only attendants upon the baths at the time of our visit were the 
washerwomen and cooks. The shores were strewed with feathers from 
the fowls that had been scalded for cooking. 
The water has no perceptible taste, and only a faint smell of sul- 
phur was observed. ‘There was no escape of gas. ‘The stones were 
covered with a white incrustation which appeared to be siliceous ; and 
a species of feathery vegetation occurs also upon them, bordering the 
streamlets where the temperature is 160° F’., and presenting various 
shades of green and white. ‘The rock of the vicinity is the tufa 
already described. 
The volcanic appearances about the Laguna de Bay evince that the 
region was once a scene of extensive eruptions. Talim, an island near 
the centre of the lake, was probably one of the volcanic summits, and 
another small island off Bay consists of the lavas of another vent. Yet 
in our short ramble we discovered no evidence that the lake corre- 
sponds to a single crater. ‘The hot springs are the only existing indi- 
cations of fire. The whole region had probably experienced subsi- 
dence, in consequence of the volcanic operations that were formerly 
in progress. On this ground, the existence of such a lake in the in- 
terior of the island is easily understood. 
The region around the Bay of Manilla has much resemblance to 
