cavities, large and small, or following 

 some underground channel or stratum, it 

 may burst forth a clear and sparkling 

 spring, or it may flow on a rivulet, or 

 river, and perhaps enter into a great sub- 

 terranean lake. The underground foun- 

 tain or lake that keeps an artesian well 

 spouting from year to year may be fed 

 by a stream or lake in the heart of some 

 distant mountain. Some artesian wells 

 cease to flow after a while, showing that 

 the fountain that supplies them is at least 

 partially exhausted. We do not know to 

 what depth water penetrates the earth. 

 Artesian wells have been bored in recent 

 years to the depth of four thousand feet. 

 The temperature of springs and artesian 

 wells is regulated by the temperature of 

 the strata through which the water per- 

 colates. The geysers of Iceland send up 

 enormous jets of hot water in the midst 

 of Arctic cold. 



The earth is nature's great filter, 

 cleansing and purifying the water from 

 the impurities of the soil. As it passes 

 through strata of gravel or clay, it be- 

 comes pure and wholesome to drink. 

 Sometimes water passes through a 

 stratum containing sulphur, iron or 

 magnesia, and so we have mineral wells 

 and springs. There is in Brown County, 

 Illinois, an iron, a sulphur, and a mag- 

 nesia spring within a few feet of each 

 other. 



Having considered underground 

 streams and lakes, artesian wells, and 

 geysers in a general way, we will now 

 proceed to notice some of the most re- 

 markable of each. Of underground 

 lakes we know but little. We cannot 

 enter them as we do a cave, and if we 

 could now and then find an entrance to 

 them, we should find little room between 

 their surface and the strata above it for 

 navigation. We infer their existence, be- 

 cause they are necessai-y to supply many 

 underground rivers and smaller streams 

 that come to the surface and discharge 

 their waters into the ocean. Another 

 proof of their existence is found in the 

 large areas of country where deep water 

 is struck at a uniform depth measuring 

 from the ocean level. The bogs of Ire- 

 land are floating upon underground 

 lakes. 



Springs are gems of the first water. 



as the dealer in precious stones would 

 say of a perfect diamond. They do not 

 impress us with their size so much as the 

 way they minister to our comfort. But 

 few wells equal them in the variety and 

 purity of their waters. I remember a 

 spring back in New England, which 

 burst forth from a bed of gravel at the 

 side of a hill with such force that it 

 seemed to fairly boil, though icy cold 

 and clear as crystal. So violent was the 

 ebullition that the gravel and pebbles 

 were continually thrown to the surface. 

 Then it ran leaping, gurgling and 

 sparkling down a steep declivity, and 

 was joined on the way by rivulets from 

 three smaller springs, so that when it 

 reached the level of the valley it became 

 a quiet, well-behaved brook, the home 

 of the speckled trout. In places where 

 it spread out over a gravelly bed the 

 birds would light upon the stones and 

 sip the water, and fly away singing joy- 

 ous notes for so exquisite a luxury. A 

 half mile from its source this brook be- 

 came quite broad and deep. It ran 

 through a pasture, and cattle came and 

 slaked their thirst. 



Hot springs are numerous in all parts 

 of the world. The water of most hot 

 springs has decided mineral properties, 

 for the reason that hot water passing 

 through mineral strata will dissolve more 

 of the mineral substance than cold water. 

 Many hot springs are great resorts for 

 invalids because of their curative proper- 

 ties. The famous Silver Spring in Flor- 

 ida has the dimensions of a small lake, 

 and boats sail over it, and a small river 

 continually flows from it. The inhabi- 

 tants of Chaudes Aigues, France, use the 

 water of the hot springs to cook their 

 food, to wash their cloths, and warm 

 their houses. The heat from these springs 

 is worth about $30 per day, as it is equal 

 to the heat produced by five tons of coal. 



Few things in nature are more beauti- 

 ful and impressive than a river bursting 

 from the hillside, its clear water 

 sparkling in the sunlight, seeming joyous 

 at bein, ' free from its captivity. Among 

 the mosL celebrated and beautiful of sub- 

 terranean rivers is the Sorgues of Dau- 

 cltise, in France. It flows for miles 

 through a cave, and discharges thirty 

 cubic yards per second. Soon after it 



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