76 



be continually changing their form, and exposing thick beds, 

 near the exterior, to alterations of temperature; the expansion 

 and contraction of these strata will probably form rents, raise 

 mountain-chains, and elevate even continents. — The author admits 

 that this is an hypothesis ; but he throws it out, that it may be sub- 

 mitted to an examination which may refute it if fallacious, — or, if 

 it be correct, establish its truth, — because he thinks that it is de- 

 duced directly from received principles, and that it promises an 

 explanation of the vast cycles presented by the phsenoraena of 

 geology. 



March 26. — William Palmer, Esq., of Essex Court, Temple, and 

 Alexander Melville, Esq., F.R.S., of Upper Harley Street, were 

 elected Fellows of this Society. 



A letter was first read from Charles Denham Orlando Jephson, 

 Esq., M.P., F.G.S., to George Bellas Greenough, Esq., P.G.S,, 

 " On Variations of Temperature in a Thermal Spring at Mallow." 



The observations recorded in this letter were made principally 

 during the autumn and winter months of 1833. The extreme 

 variations were 67° and 71°tV5 the difference depending, in Mr. 

 Jephson's opinion, on the quantity of water acted upon. From 

 80 to 100 yards north of the spring at which the observations 

 were made, are other thermal springs, the temperature of which 

 is 1° higher, and from 60 to 80 yards to the south is a cold spring, 

 having a temperature of 54)°. The formation from which the waters 

 issue is limestone. 



A letter was then read from William Henry Egerton, Esq., 

 F.G.S., addressed to Charles Lyell, Esq., For. Sec. G.S., " On 

 the Delta of Kander." 



The Kander in its ancient course flowed parallel to the Lake of 

 Thun, and emptied itself into the Aar, beyond the village of 

 Heimberg ; but in consequence of the injury done to the land by 

 its frequent inundations, the Government of Bern determined to 

 direct its waters into the lake of Thun. This object was finally 

 accomplished about the year 1713, by making two parallel tunnels, 

 about a mile in length, between the original course of the river and 

 the lake ; and no sooner was the Kander admitted into them than 

 it burst up the arches, tore away the masses of rock which ob- 

 structed its passage, and bore a vast heap of gravel and detritus 

 into the lake. The delta thus commenced, and increased by the 

 sedimentary matter brought down during nearly 120 years, now 

 presents a tract covered with trees, extending about a mile along 

 the original shore, and a quarter of a mile from it into the lake. 

 The depth of the ravine by which the Kander now enters the lake 

 is 50 feet. The depth of water at the part occupied by the delta 

 Mr. Egerton could not ascertain, but, from the declivitj^ of the 

 ancient banks, he conceives that it must have been consider- 

 able, and Saussure found some parts of the lake to be 350 French 

 feet in depth. The author determined by actual measurement the 

 angle at which the new deposit dips beneath the waters of the lake, 



