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BACON. 



differ from the waters of the crater lake proper, as the formation appears 

 as if it were merely a part of the crater lake which had been, filled in 

 with colored salts through which the water still reached the surface in 

 the remaining pools. This curious and beautiful formation is shown by 

 Plate V, fig. 3, and Plate VI, fig. 2. 



Water No. 3, from the green lake, is of a very deep, green color, it has 

 a very strong, acid taste and, as obtained, it contained considerable sedi- 

 ment. However, farther from the shore the water is clearer. The sedi- 

 ment is largely clay and gypsum. All around the edges of this lake 

 and covering the bottom near the shore, is a very abundant growth of 

 gypsum crystals; the ones on the shores of the lake being colored yellow 

 by iron salts. 



Qualitative analyses demonstrated that all three waters contained the 

 same elements, ferric and ferrous iron, aluminium, magnesium, calcium, 

 strontium, barium (spectroscope), ammonium (small amount only), 

 potassium, sodium, sulphuric and hydrochloric acids, and phosphoric acid 

 (traces). No caesium or rubidium or other rare or unusual elements 

 could be detected by spectroscopic examination. The quantitative ana- 

 Ivses are as follows : v 



Table No. 1. — Quantitative analyses of water from the crater of Taal volcano. 



[Figures express grams per 100 cubic centimeters of the water.] 



No. 1. No. 2." 



Color Light grayish green. Green. 



Sp.gr. at 15° 1.072 1.081 



Acidity 1. 33 N. 1. 335 N. 



Acidity calc. as H 2 S0 4 

 Calc. as HC1 



Total solids (filtered water) by heat- 

 ing to 110° for six hours 



8.576 



6.54% 

 4.87% 



10. 1402 



No. 3. 

 Green. 

 1.158 

 1. 78 N. 

 8.72% 

 6.49% 



19.7: 



• 8» 



Per cent. Per cent. Per cent. 



Chlorine, CI 4. 7512 4. 8925 10. 9312 



Sulphuric ions, SO " 4 3.0808 1.9688 2.3542 



Ferrous iron, Fe . 5148 . 8367 1. 1960 



Ferric iron, Fe .0009 .0843 .1486 



Total iron .5157 .9210 1.3446 



Aluminium, Al . 7622 . 8978 2. 0927 



Calcium, Ca . 2813 . 2082 . 1328 



Magnesium, Mg . 0318 . 4343 . 1514 



Sodium, Na . 7419 . 7192 2. 3246 



Potassium, K . 0125 . 0048 . 0104 



Loss on evaporating to total solids 2. 1171 . 8284 . 8985 



The "acidity" of these waters, as was that of the waters analyzed a year 



N 

 ago, was determined by titrating with — - alkali, using phenolphthale'in 



as an indicator, and hence it does not represent the true acid value or even 

 the extent of hydrolysis of salts taking place in these waters. This 



