UZ ON: BAL 
In the interior, twelve miles south of east from Manilla, there is a 
fresh-water lake called Lagunade Bay, covering an area of nearly four 
hundred square miles. A large stream flows from it, and passing in 
several wide channels through the city of Manilla, empties into the 
harbour. 
One of the interesting points about this lake is the fact that vast quan- 
tities of floating plants live on its surface, and pass down the river into 
the bay, carrying along great numbers of fresh-water snails of differ- 
ent species. Here we have, therefore, fresh-water shells and vegeta- 
tion which is not marine, accumulating under salt water, for they sink 
after a while, and must become buried in the mud of the bottom along 
with the remains of marine life. ‘This floating vegetation illustrates 
a theory with regard to the vegetation of the coal beds; and it cer- 
tainly gives the view strong support, as we have remarked when speak- 
ing of the coal of Australia. 
From this digression, we return, mentioning a few facts relating 
to other parts of the island before describing more particularly the 
vicinity of the Laguna de Bay. The Laguna de Taal is a similar lake, 
twenty miles farther south, averaging twelve miles in diameter, and 
covering an area of one hundred miles. It contains a volcano still 
smoking, the Volcano de Taal. The cone, as I was informed by 
residents on the island, is about nine hundred feet high. ‘The crater 
has about the same depth, with perpendicular sides, and is near two 
miles in diameter. At the bottom of the crater there are two small 
cones and many smoking fissures. ‘The crater is reputed to afford 
pure native sulphuric acid, in addition to sulphur and some volcanic 
salts. There are also several other cones about the lake. 
Southeast of this lake the island is said to be wholly volcanic, and 
in this part, towards the southeast corner, stands the high cone of 
Albay, called by the natives Mount Isaroc, whose eruptions in 1814 
covered with ashes a large extent of country and several villages. It 
is a steep but regular cone about three thousand feet high; it still 
smokes and occasionally discharges cinders. 
Volcano de Taal and Mount Isaroc are the only active volcanoes in 
the southern part of Luzon. ‘To the north there is a crater in the 
northern province of Xocolos, which has been in eruption since the 
Spaniards first arrived on the island, but is now quiet. 
The broad plains of Manilla are, for the most part, underlaid by an 
ash-coloured tufa, and even over its lower parts, where no sections ex- 
hibit this tufa to view, the soil appears to have been derived from the 
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