Mr. Horner on the Geology of the Environs of Bonn. 459 



beat and trodden after being well mixed with water, and is formed in shapes 

 like the crown of a small hat, which are laid out to dry like bricks, and these 

 when dry are preserved for use by being piled up under cover. In this state 

 they are called Klutten, and are sold on the ground for about nine groschen 

 per hundred ; and as each of the klutten weigh about five pounds when dry, 

 the price is equal to about four shillings per ton *. 



The beds of the brown-coal formation are generally either horizontal or 

 deviate only a few degrees from it. In the immediate neighbourhood of Ut- 

 weiler, however, under a bed of loess about fourteen feet thick, there is a se- 

 ries of about twenty distinct strata of clay, distinguished by various colours, 

 and containing four layers of lignite, each about six inches thick, which have 

 an inclination about 60° S. This elevation was probably occasioned by the 

 eruption of basalt which is in the immediate neighbourhood. On the left 

 bank of the Rhine, and near Briihl, near which no unstratified rocks appear, 

 there have been also considerable disturbances subsequent to the deposition 

 of the beds. At Hennersgrube, near the old monastery of Beuten, the lignite 

 beds are suddenly cut oflf by a fault to the depth of forty-nine feetf. 



By referring to the Map, it will be seen that the brown-coal formation exists to a considerable 

 extent within the volcanic region of the Siebengebirge, especially in the valley of Haisterbach. It 

 is found in two small patches in Konigswinter valley, one at a place called Kuckstein, pretty high 

 up in the ascent to the Drachenfels, where clay beds are found ; the other in the bottom of the 

 valley at Quegstein and Tanzchen, as already mentioned. Here the sandstone members of the 

 series only occur, the quartzose conglomerate occurring in great detached masses, seemingly piled 

 together. These probably formed indurated portions in a deposit of sand, which has been since 

 washed away, as has been often noticed in sandy beds of the plastic clay and other tertiary de- 

 posits. 



In the southern parts of this district the brown-coal formation occupies much higher situations. 

 The Papierkohle of Orsberg, near Erpel, which contains the impressions of reptiles and insects, is 

 372 feet above the Rhine ; and continuing the ascent towards Bruckhausen, there is a plateau of 

 about a mile square, which seems to be entirely composed of the brown coal formation. At the 

 very foot of the Mendenberg, at Ehl and at Stosschen, there is a very extensive deposit of lignite 

 on the slope of the mountain, very high above the adjoining valleys, which has long been worked 

 for the purpose of making alum, the clay and lignite being highly pyritous. The latter splits into 

 thin plates, and contains numerous impressions of leaves, and occasionally those of insects, and is 

 about sixteen feet thick. The beds occur close to the basalt ; and the workmen told me that they 

 rise towards it, but that the actual contact is not seen. It appears that formerly four different beds 



* The pigment called Cologne earth is prepared from an earthy lignite. It is said that a great 

 quantity of the light pulverulent varieties is sent to France and Holland, to be used in the adul- 

 teration of snuff. 



t Von Dechen, in Karsten, uti supra. 

 VOL. IV. SECOND SERIES. 3 O 



