Scientific Meeting in Germany. 28*7 



ing and serial arrangement of these mountains in accordance with 

 these lines of elevation, was regulated by the same laws which 

 regulated the foundation and successive completion of the moun- 

 tain systems and ranges of every portion of the earth's surface. 

 In conformity with these principles, Dr. Abich maintained that 

 every view was to be rejected which might incline to refer the 

 eruptive phenomena which still retain their permanent seat in the 

 bosom of these formations to so-called secondary causes, that is, 

 in the present case, to any other causes than such as depend upon 

 Vulcan ism. 



Herr Ignatius Beissel spoke on the marl of Aix-la-Chapelle, and 

 laid before the section a geological collection from the Friedrichs- 

 berg and the Willkomrasberg, in the neighbourhood of that city. 

 The distinction hitherto assumed between the Aix and Bohemian 

 chalk on the one hand, and the Westphalian on the other, ground- 

 ed on the occurrence of polythalami and cirrhipoda in the for- 

 mer, must now be done away with. Ehrenberg's discovery that 

 marl consists of organic bodies is confirmed. The green sand has 

 arisen from a marly rock by the loss of its carbonate of lime. Down 

 to the present time the marl is passing inio sandbeds under the in. 

 fluence of fresh water. The proofs which he adduced were : — 1. 

 Those fossils which characterise the green sand are found in banks 

 of sandstone which have lost every particle of lime, in banks of 

 sandstone containing lime, in the banks of Dumont's psammite 

 glauconifere. 2. The speaker had himself found the characteristic 

 fossils of the upper beds of the Aachen chalk in dry deposits of 

 green sand. 3. The glauconite granule is in most cases the re- 

 sult of the formation of a stone nucleus in the shells of polythala- 

 miae. 4. On dissolving the marl in muriatic acid we obtain a re- 

 siduum of green sand. That the lower portions of the chalk are 

 precisely those which have lost their lime is explained by the cir- 

 cumstance that, being the last to be elevated above the sea, they 

 were the longest exposed to the influence of the sea-water ; more- 

 over the meteoric waters flow over the clay strata of the Aachen 

 sand, and thus fill the lower division while they merely filter 

 through the upper. The speaker then discussed the residuum of 

 the marl and green sand : — 1. The double refracting siliceous splin- 

 ter ; 2. The single-refracting spongiolites. The siliceous splinters 

 originate : — 1. From spongiolites which become crystalline on the 

 change of the amorphous silica ; 2. From the disintegration of the 

 white stone granules of polythalamia3 ; 3. From glauconite gra- 



