TWEXTY-SIXTH AXXUAL MEETING. 37 



Silica and insoluble matter 19.30 



Peroxide of iron and alumina 46.95 



Calcium oxide 4.20 



Magnesium oxide 34 



Sulfuric anhydride 15 



Water, driven off below 100 degrees C 9.15 



Water, driven off above 100 degrees C 14.40 



Chlorin 31 



Carbonic anhydride 3.12 



Sodium oxide (calculated) 39 



The most probable combination is the following: 



Silica and insoluble matter 19.30 



Iron and alumina oxides *46.95 



Calcium sulfate 25 



Calcium carbonate 7.32 



Magnesium carbonate 75 



Sodium chlorid 60 



Water, driven eft at 100 degrees C 9.15 



Water, driven off at 230 degrees C 14.40 



Organic matter (undetermined) 1.28 



Total 100.00 



From an examination of these analyses it can be seen that the silica is re- 

 tained in solution to a much larger extent than the iron; the part of the silica 

 retained, however, being only a portion of that dissolved in the original 

 vfa.ter, as is shown by the character of the deposit. 



The copious deposit of iron is a very instructive illustration of how much 

 of this substance the underground water, saturated with carbon dioxide, can 

 hold in solution, and the ease with which it is deposited on the slightest con- 

 tact with air. The sulfates and the sodium chlorid are deposited only to a 

 limited extent, while carbonates of calcium and magnesium are deposited 

 freely. This latter deposition would be expected, since the excess of carbon 

 dioxide has had an opportunity to escape, thus precipitating the carbonates. 

 This is then a process of softening, as far as those substances that make up 

 what is known as the temporary hardness of the waters is concerned. 



The presence of a large quantity of water, and especially the character- 

 istic amount given off at 230 degrees C, shows that the deposit is practically 

 an ore of iron, in fact, limonite. This might be considered as transported 

 from the surrounding gravel as such, were it not that the water is so clear 

 when it first runs into the well, so it is more rational to believe that the iron 

 is first dissolved in the highly carbonated water, for in the freshly drawn 

 water it is always present in the ferrous state, and is later oxidized to ferric 

 iron and at the same time deposited. Upon heating the deposit a dark red- 

 dish paint is obtained. It might be supposed that there would be a large 

 amount of organic matter in this deposit, since there is no doubt that the 

 organic substances in the soil have played a very important part in the 

 changes that the water has undergone, but on examination with the micro- 

 scope no organized organic remains can be discovered. 



♦Nearly all oxide of iron. 



