68 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



ellipse and not a circle, favor the idea that in these earlier 

 epochs this ellipticity must have assumed the nature of a 

 gradual change in the figure of the earth, in virtue of which 

 a vast equatorial undulation has progressed with extreme 

 slowness in an easterly and westerly direction. 12 A, X., 

 166. 



UNDERGROUND TEMPERATURES. 



The sixth report of the committee on underground tem- 

 peratures states that they have made a very interesting 

 series of observations in the great well of La Chapelle, at 

 Paris. There was a tolerably regular increase of tempera- 

 ture at the average rate of one degree Fahr. for every nine- 

 ty-four feet, except for the very last portion of the well, where 

 a sudden increase appeared to take place, giving a rate of 

 about one degree for every twenty-five feet. A very elabo- 

 rate calculation has been made by the engineers in charge 

 of the well, which has shown that a large portion of this 

 sudden increase of temperature must be attributed to the 

 heat generated by the operation of boring the well. The 

 total weight of the tool employed by them is 3000 kilo- 

 grammes, and the quantity of work converted into heat at 

 every fall of this great weight through a distance of fifteen 

 inches is sufficient to raise the temperature of the lower 

 portion to nearly 100 Fahr., which heat is retained at 

 the bottom of the well for many days, owing to the feeble 

 conducting power of the surrounding rocks. Report Brit. 

 Assoc, 1873, 252. 



"ice cave" near dobsciiau. 



Dr. Joseph A. Krenner, of the National Museum of Bu- 

 da-Pesth, gives an account of a visit to the famous ice cave 

 near Dobschau, in the spring of 1873. It is located in the 

 " Goellnitzer" valley, and is excavated in triassic limestone. 

 From the entrance the trend of the cave is downward, a 

 large mass of stratified ice, partly transparent, partly trans- 

 lucent, forming the floor of the higher and larger portions, 

 while numerous stalactites and stalagmites of ice (the former 

 hollow) ornament the ceiling and walls, forming a*t times ex- 

 ceedingly picturesque groups. Frozen waterfalls are found 

 near the lower portions of the cave. The ice which serves 



