GEOLOGY. 235 



removed the water would be decomposed and the carbon vaporized. 

 If, as we have reason to suppose, the sea floors constantly bend 

 downwards by vh'tue of the forces brought into action by the depo- 

 sition of strata, there would naturally be a tendency to fracture 

 along the shore line. Such fissures penetrating to the bed of these 

 pent-up gases would give them relief. The reconstruction of the 

 oxygen of the water, taking place at a distance from the point of 

 decomposition, with the gaseous carbon, would generate heat 

 enough* to melt the walls of the channel, and this molten matter 

 would be pushed out by the escaping gases. 



All, or nearly all, volcanic eruptions begin with a rush of gases. 

 After an interval, which may be supposed to correspond to the 

 time required for the molten rock to accumulate and clog the 

 channel, comes an outbreak of lava, succeeded, if the eruption 

 continues, by another rush of gases, followed, it may be, by an- 

 other escape of molten matter. The character of the gases poured 

 out during an eruption corresponds very well with what would be 

 required by this theory. — Abstract of a View presented in a Course 

 of Lectures at Harvard College, hy Prof. N. S. Shaler. 



THE FROZEN WELL AT BRANDON, VERMONT. 



Descriptions of this well have been published in the "Annual 

 Sci. Disc," 18G0, p. 316; ibid., 1856, p. 190. In the "Hours at 

 Home" for Feb., 1870, there isan article upon this well. The scien- 

 tific observations will be of interest. We condense the following 

 from aj^aper presented to the American Academy of Arts and Sci- 

 ences, by Prof. F. H. Storer, in behalf of Prof. John M. Ordway 

 and himself, and contained in vol. v. (Records from May, 1860, to 

 May, 1862) of the proceedings of that body. 



** On visiting the locality in the early part of the summer of 

 1860, we ascertained the existence of a variable but well-marked 

 current of cold air continually flowing upwards out of the mouth of 

 the well. Bits of any light material dropped in were buoyed up and 

 forcibl}^ blown out. The mature pappus of the dandelion, which 

 was then in full puft' all around, aflorded an abundance of very 

 sensitive current indicators. 



"At the opening of the well the thermometer indicated 43.5° F., 

 the temperature of the external air being 78°. Five feet below the 

 mouth, the thermometer stood at 43°, and 12 feet down, at 40°. 

 Water drawn up from the bottom, without stopping to cool the 

 bucket, was at 34°. Water drawn up at other times contained 

 lumps of ice detached from the coating of ice lining the well to the 

 height of some 5 feet above the surface of the water. 



** We had hardly begun to make close observations, before it 

 occurred to us that we were dealing with a case of compressed 

 air, which might be accumulated l^y some natural subterranean 

 Trompe (Wassertrommel), or "Catalan blower," and which. 



