376 Dr. Thomas on the Amber Beds of East Prussia. 



for under this sand-bank, consisting of parallel layers and about 

 twenty feet thick, extend in a similar direction the strata of 

 mottled and blue amber-earth, streaks of sandy loam about two 

 feet thick, which in consequence of their great abundance of 

 amber are everywhere explored, where they rise sufficiently high 

 above the surface of the sea. Under them is found the bed 

 called Schluff, which is distinguished from the amber-beds 

 merely by the absence of amber. Amber however is not wanting 

 in the muscle-bearing bed of sand which lies above it, by whose 

 concretions it is often surrounded as by a matrix, but always 

 much worn by the atmosphere. In the subjacent loam-beds, 

 which may be regarded as the primary amber-strata, it is mostly 

 in a state little differing from its original condition. The dull 

 surface which covers with a thicker or thinner layer the shining- 

 resin within, exists in pieces of copal and pine-resin, and cannot 

 be ascribed to any action of the weather, or have been produced 

 by the agency of decomposing substances which have acted for 

 thousands of years. The dull bark investing amber, copal and 

 other resins in their natural condition is a partial alteration 

 which they undergo from the influence of the atmospheric oxygen 

 soon after their production, and, except where something hinders 

 the progress of this decomposition, it proceeds till the original 

 structure is entirely deranged. Such is the case in the super- 

 ficial strata of our present soil, in which the amber accidentally 

 present is always highly decomposed, and such also in those beds 

 of sand which form the capping of the primary amber-beds. As 

 regards the occurrence of fossil vegetable remains in these strata, 

 they are very scarce in the muscle-bearing sand. Carbonized 

 wood is somewhat more frequent in the amber-beds, at present 

 entirely coniferous, and probably of the same structure as in 

 the beds near Eauschen. But while this coal belongs to the 

 class of earthy lignite, the carbonized ligneous remains of the 

 amber-beds exhibit rather the condition of anthracite. Extra- 

 neous marine remains seem not to be entirely wanting in these 

 amber-bearing beds. Sharks' teeth especially have been dug at 

 times from the amber -pits, known under the name of birds' beaks; 

 and impressions of Echinites, now unfortunately lost, were col- 

 lected by me in the Schluff of the amber-pits at Little Kuhren. 

 Another specific character as it should seem of these strata is their 

 surprising abundance in sulphurous salts, as recognized by the 

 strong taste of ink and the efflorescence of those portions which 

 have been long exposed to the atmosphere. 



This member of muscle-bearing sand, spotted and blue amber- 

 earth and Schluff extends at the above-mentioned angle of eleva- 

 tion under the villages of Great and Little Kuhren, where it rises 

 from forty to sixty feet above the surface of the sea, and to the 



