﻿120 BACON. 



a little over a year ago, have stood in the laboratory in tightly closed 

 bottles. The temperature of Manila varies only a few degrees during 

 the year and in the laboratory one could safely state that the variation 

 of temperature to which these bottled waters have been subjected has 

 not been over 10° C. Nevertheless, a large amount of sediment, which 

 was foiuid to consist of aluminium hydrate and a little gypsum, had 

 collected in each of the containers, and 3 liters of carefully filtered Water 

 No. 3, left standing for one week in a tightly closed, glass-stoppered 

 bottle, had deposited nearly 1 gram of sediment which also consisted of 

 gypsum and aluminium hydrate. 6 



Very extensive deposits of a fine quality of kaolin are found in the 

 immediate neighborhood of Taal volcano, near Los Banos and between 

 Mount Maquiling and Taal Lake. It is suggested that these were prob- 

 ably deposited as a result of the disintegration of feldspars and other 

 aluminous minerals by hot, volcanic waters, just as the Taal waters are 

 now depositing compounds of aluminium. 



The aluminium, magnesium, calcium, and iron in the Taal waters can 

 readily be accounted for as a result of the action of acid waters on the 

 feldspar rocks in the immediate neighborhood and the nature of the 

 efflorescent deposits found on rocks around the crater lake and the various 

 fumaroles makes such an assumption probable. It is at first difficult to 

 imagine that the laxge quantity of chlorine could have had its source in 

 anything but common salt, but the amount of sodium present in the 

 waters is sufficient to combine only with approximately 0.2 to 0.33 of 

 the chlorine, so that if the latter element really originated from sodium 

 chloride, much of the sodium must have been taken up to displace other 

 elements in the passage of the water through the rocks. Calcium seems 

 the most probable element to have been so displaced, as gypsum crystals 

 are growing very vigorously both in and around the lakes, and it is 

 well known that an alkali metal, or a metal of the group of alkaline earths, 

 can readily be displaced by another metal of one of these groups, the 

 direction of the reaction depending upon the concentration of the ele- 

 ments in the surrounding waters and taking place according to the 

 general laws of mass action. 7 Etimpler s was able to displace calcium 

 by the alkali metals, on filtering sugar saps through various silicates, and 

 he proved that the reaction was one which was readily reversible, its 



6 The extensive French deposits of bauxite are ascribed by Coquard and Angi 

 to hot, mineral springs and geysers which dissolved the alumina and brought it 

 to the surface. Hays ascribes the Georgia, Alabama, and the Arkansas deposits 

 to the action of waters containing sulphuric acid, on aluminous shales and 

 feldspars, the waters probably being neutralized by limestone after reaching the 

 surface. 



'Van Hise: A Treatise on Metamorphism. Monograph U- 8. Geol. Survey 

 (1904), 252. 



8 Riimpler: Ztschr. Ter. Rubenzuck. Ind. (1903), 798. 



