Vokanos and Earthquakes. 383 



water. For instance, while the water of the above-mentioned 

 sinking brooks and rivers penetrates into the interior of the 

 hills with the variable temperature of the seasons, the waters of 

 the numerous springs of Faderborti, whose mean temperature is 

 50°.6 F, and exceeds the mean temperature of the soil by about 

 1°.7, present already a uniform degree of heat. Thus, on the 

 21st ^ay 1834, I found the temperature of the Jlme at Bren- 

 ken, where considerable masses of the water of this river flow 

 down through the clefts of the chalk, to be 63"^, while the springs 

 at Geseke, at the distance of 22,000 feet, which doubtless re- 

 ceive their supply from this river, were of the temperature of 

 49° to 51°. The miller there, whose mill is turned by one of 

 these springs (what is called the Volmeder spring), told me he had 

 often opened the holes found on the banks of the Alme, and let 

 in as much water as would have been alone sufficient to turn 

 his mill, but that he never perceived the slightest increase of 

 the streams. This also proves the great extent of the subter- 

 raneous reservoir of water, whose discharges are not percepti- 

 bly increased by an addition of water. If, indeed, these addi- 

 tions are continued by continued wet weather, and the level 

 of the subterraneous reservoir rises, then, not only will those 

 springs become more copious, but water will also issue from 

 high-situated channels, which contained no water during the 

 dry season. Lastly, the same miller assured me that the 

 muddiness of his mill-streams by no means depended on that 

 of the Alme^ since they always become so after rain. Opi- 

 nions were, however, divided on this point, as other inhabit- 

 ants of Geseke maintained , that, within twelve or sixteen hours 

 after rain, the Alme became muddy, and the Volmeder springs 

 became so too, while this had no influence on the springs in the 

 town. Be this as it will, thus much is certain, that all the 

 springs there do not become muddy after rain, but that many 

 always remain clear, as the warmer among the Pader springs. 

 This circumstance is also a satisfactory proof of the great ex- 

 tent of the subterraneous reservoir, because, notwithstanding 

 the fact, that the sinking rivers and brooks, as well as the rain- 

 water and snow-water, which penetrate into the fissures of the 

 fissured rock, are all muddy in rainy weather, yet the warmer 



