B. TERRESTRIAL PHYSICS AND METEOROLOGY. 101 



atmospheric circumstances. These changes, it is suggested, 

 are probably due to the modifications that have taken place 

 in the course of years in the hydraulic works, and the drain- 

 age of the neighborhood. There seems to be no trace of such 

 a change as Mr. Dawson states that he has found in the levels 

 of the Great Lakes of North America, according to whom 

 these vary in a period of about eleven years, following closely 

 the changes in the solar spots. Mem. Soc.Phys. Geneva, 18V 4. 



THE ELECTRICAL CONDITION OF SPRING WATER. 



Messrs. Theury and Minnich state that they have employ- 

 ed a delicate galvanometer in making some experiments on 

 the electricity of the warm springs in Baden and Switzer- 

 land. One of the platinum electrodes was plunged into the 

 upper spring at Stadthof, and the other electrode into the 

 little stream Limbat. As soon as the metallic connection 

 was completed, the needle of the galvanometer moved vio- 

 lently, oscillating about 74; then in proportion as the elec- 

 trode was covered with bubbles of gas, and became polarized, 

 the galvanometer needle descended to 72, and even to 60, 

 ascending to 70 when the electrode was cleansed of bubbles 

 with a brush. This experiment shows that the thermal wa- 

 ter was very strongly electrized, the source of the water be- 

 ing negative. Again, placing two vases of water side by 

 side, the first vase filled with spring water, taken immediate- 

 ly from the source and still quite warm, the second vase fill- 

 ed with cold w r ater from the river, the platinum electrodes 

 were introduced, and immediately the needle of the galva- 

 nometer indicated a current flowing from the cold to the 

 warm vase ; that is, in the same direction as the current 

 of the spring, the warm spring water being electrized nega- 

 tively. When the spring water had completely cooled, it 

 was again heated with an alcohol lamp to a temperature of 

 47, and the electrode immersed, but without observing any 

 appreciable current in the galvanometer. 1 J3, XV., 411. 



ON THE SECULAR DIMINUTION IN EUROPE OF SPRINGS, RIVERS, 

 AND STREAMS, WITH THE SIMULTANEOUS INCREASE IN THE 

 FLOOD WATERS IN CULTIVATED LANDS. 



A memoir by Gustave Wex, published at Vienna in 1873, 

 on the diminution of water in springs and rivers, and the in- 



