206 COSMOS. 



advanced of late years, by the successful employment of 

 chemistry, in the geognostic investigation of the formation 



Of the springs of Marienberg 4 belong to the group of purely meteoro- 

 logical springs, of these 4 one is undistorted in its average, the three 

 others are approximated in various degrees. In the first year of obser- 

 vation the portion of rain of the cold third predominated, and all four 

 springs were on the average colder than the air. In the four following 

 years of observation the rain of the warm third predominated, and in 

 these all the four springs had <t higher average temperature than the 

 air; and the positive variation of. the average of the spring from that 

 of the air was higher, the greater the excess of rain in the warm third 

 of one of the four years. . 



" The view put forward in the year 1825, by Leopold von Buch, that 

 the amount of variation of the average of springs from that of the air 

 must depend upon the distribution of rain in the seasons of the year 

 has been shown to be perfectly correct by Hallmann, at least for his 

 place of observation, Marienberg, in the Rhenish Grauwacke mountains. 

 The purely meteorological springs of undistorted average alone have 

 any value for scientific climatology ; these springs are to be sought for 

 everywhere, and to be distinguished on the one hand from the purely 

 meteorological springs with an approximate average, and on the other 

 from the rneteorologico-geological springs. 



"2. Meteorologico-ge-jlogical springs: that is to s.ay, those of which 

 the average is demonstrably heightened by the heat of the earth. What- 

 ever the distribution of rain may be, these springs are in their average 

 warmer than the air, all the year round (the alterations of temperature 

 which they exhibit in the course of the year are communicated to them 

 by the soil through which they flow). The amount by which the 

 average of a rneteorologico-geological spring exceeds the atmospheric 

 average, depends upon the depth to which the meteoric waters have 

 sunk down into the interior of the earth, where the temperature is con- 

 stant, before they again make their appearance in the form of a spring ; 

 this amount consequently possesses no climatological interest. The 

 clirnatologist must, however, know these springs, in order that he may 

 not mistake them for purely meteorological springs. The meteorologico- 

 geological springs may also be approximated to the aerial average by an 

 enclosure or channel. The springs were observed on particular fixed 

 days, four or five times a month. The elevation above the sea, both of 

 the place where the temperature of the air was observed, and of the 

 different springs was carefully taken into account." 



After the completion of the elaboration of his observations at Marien- 

 berg, Dr. Hallmann passed the winter of 1852 1853 in Italy, and 

 found abnormally cold springs in the vicinity of ordinary ones. This is 

 the name he gives "to those springs which demonstrably bring down 

 cold from above. These springs are to be regarded as subterranean 

 drains of open lakes or subterranean accumulations of water situated 

 at a great elevation, from which the waters pour down very rapidly 

 in fissures and clefts, and break forth *t the foot of the mountain or 

 chain of mountains in the form of springs. The idea of the abnormally 



