196 COSMOS, 



One of my intimate friends, a highly endowed scientific 

 observer, will, I hope, before long publish a new and import- 

 ant work upon the conditions of temperature of springs, and 

 in it treat with great acumen and universality, by induction 

 from a long series of recent observations, upon the involved 

 phenomenon of disturbances. In the determinations of tem- 

 perature made by him in Germany (on the Rhine) and in 

 Italy (in the vicinity of Rome, in the Albanian mountains 

 and the Apennines) from the year 1845 to 1853, Eduard 

 Ilallmann distinguishes : 1. Purely meteorological springs, the 

 average temperature of which is not increased by the internal 

 heat of the earth ; 2. Meteorologico-gcological springs, which, 

 being independent of the distribution of rain, and warmer 

 than the air, only undergo such alterations of temperature as 

 are communicated to them by the soil through which they 

 flow out ; 3. Abnormally cold springs, which bring down their 

 coldness from great elevations.* The more we have advanced 



bcr, appear to have been formed by solution, while the veins filled with 

 concretions of metal seem to be nothing but immense canals more or 

 less obstructed, and formerly traversed by incrusting thermal waters. 

 The formation of a great number of minerals which are met with in 

 these lodes does not always presuppose conditions or agents very far 

 removed from existing causes. The two principal elements of the most 

 widely-diffused thermal waters, the alkaline sulphurets and carbonates, 

 have enabled me to reproduce artificially, by very simple synthetic 

 methods, 29- distinct mineral species, nearly all crystallized, belong- 

 ing to the native metals (native silver, copper, and arsenic), quart/,, 

 specular iron, carbonates of iron, nickel, zinc, manganese, sulphate 

 of baryta, pyrites, malachite, copper pyrites, sulphuret of copper, red 

 arsenical and antimonial silver. . . . We approach as closely as pos- 

 sible to the processes of nature, if we succeed in reproducing minerals 

 in their conditions of possible association, by means of the most wide- 

 ly diffused natural chemical agents, and by imitating the phenomena 

 which we still see realized in the foci in which the mineral creation 

 has concentrated the remains of that activity which it formerly dis- 

 played with a very different energy." (H. de Senarmont, Sur la Forma- 

 tion des Miner aux par la Vole llumide, in the Annales de Chemie ct de 

 Physique, 3e serie, t. xxxii., 1851, p. 234 ; see also Elie de Beaumont, 

 Sur les Emanations Volcaniqucs et MetalliJ'eres, in the Bulletin de la 

 Socicte Geoloyique de France, 2e serie, t. xv., p. 129.) 



* " In order to ascertain the amount of variation of the average 

 temperature of springs from that of the air, Dr. Eduard Hallmann ob- 

 served at his former residence, Marienberg, near Boppard, on the 

 Rhine, the temperature of the air, the amount of rain, and the tem- 

 perature of seven springs for five years, from the 1st December, 1845, 

 to the 30th November, 1850 ; upon these observations he has founded 

 a new elaboration of the relative temperature of springs. In this in- 

 vestigation the springs with a perfectly constant temperature (the 

 purely geological springs) are excluded. On the other hand, all those 



