375 



Annuaire de I'Acadeinle Royale des Sciences et Belles Lettres de 



Bruxelles. Pour I'An. 1842. 

 Bulletin de rAcademie Royale des Sciences et Belles Lettres de 



Bruxelles. 1841, Nos. 7-12; et 1842, Nos. 1, 2.— By the 



Academy. 

 Maanetische und Meteorologische Beobachtungen zu Pracr. Heraus- 



gegeben von Karl Kriel. Erster Jahrgang. — By the Author. 

 Philosophical Transactions of the Royal Society of London, for the 



Year 1841. Part 2. — By the Society. 

 Examination Papers of the University of London for 1841. — By 



the University. 

 Plausible Reasons and Positive Proofs, shewing that no portion of 



the Devonian System can be of the age of the Old Redstone. 



By the Rev. D. Williams, A.M., F.G.S. — By the Author. 

 The Reminiscences of an Old Traveller throughout different parts 



of Europe. By Thomas Brown, Esq. — By the .Author. 



Monday, April 18, 1842. 



The Right Hon. Lord GREENOCK, V.P., in the Chair. 



The following communications were read : 



1. On the Structure, Formation, and Movement of Glaciers ; 

 and the probable cause of their former extension and subse- 

 quent disappearance. By James Stark, M.D., F.R.S.E. 



The author endeavoured to prove, from the recorded facts stated 

 by different writers, that the crystalline particles of which the ice 

 of glaciers is composed do not sensii)ly enlarge after being consoli- 

 dated into compact ice ; that the crystals have been shewn to be 

 fully and perfectly formed in the course of a few nights in the 

 Polar Regions ; and that they have a position perpendicular to the 

 layer of ice which they form, — their length being thus determined 

 by the thickness of that layer. 



The author next considered the different forms of stratification 

 met with in glaciers, and stated that the greatest confusion prevailed 

 on this point, different forms of stratification being confounded to- 

 gether. He therefore considered glaciers as composed of — 



1. Horizontal Strata, or layers lying in the position in which 

 they were first deposited, and only seen in the upper regions of the 

 mountains. He stated that these strata were usually regarded as 



