ON THE CIRCULATION OF UNDERGROUND WATERS. 79 



Magnesia 0-000 



Lime 4-209 



Sulphuric acid 1-795 



Silica -914 



Carbonic acid 3-302 



Organic matter and loss 4-015 



19-427 

 Hardness 7 0, 5 



The proportion of mineral salts, and especially of the hardening salts, car- 

 bonate of lime and sulphate of magnesia, has increased very nrach since 1850, 

 and is still increasing as the well is pumped to a lower level. The deep 

 water is rather harder than the upper water. 



No. 1, Bevington Bush, water out of the lodgment at bottom of well. 

 January 31, 1850. 



Chlorine 19-526 



Sodium 12-660 



Magnesia 6-911 



Lime 11-386 



Sulphuric acid 10-084 



Silica -571 



Carbonic acid 11-004 



72-142 

 Hardness 40°-86. 



^Votc. — The nitrates seem to have been overlooked in this analysis. 



The well has long ago been closed. 



I analyzed this well for the Water Committee in 1 868, when it contained 

 - — total solids 70, nitric acid 12, hardness 36°. The well must have con- 

 tained nitrates in 1850, which have been overlooked ; these salts, as well as 

 the chlorides, undoubtedly come chiefly from urine and other sewage matter 

 with which the ground around the well is saturated. Some of the chlorides 

 might formerly have come from the sea, but there is no evidence whatever to 

 show that they do. 



No. 3, Copperas Hill, water from lodgment at bottom of well. 

 January 21, 1850. 



Chlorine 6-153 



Sodium 3-990 



Magnesia 4-965 



Lime 8-887 



Sulphuric acid 6*355 



Silica 1-371 



Carbonic acid 8-951 



Organic matter, traces of potash, water 



of crystallization, and loss 5-S4."» 



46-515 



