378 Dr. Thomas on the Amber Beds of East Prussia, 



small specimens which I have observed in the rich collection of 

 Privy Councillor Hagen seem to indicate such a difference. 



If then we allow the existence of an amber-formation which 

 contains primary beds of amber of a greater antiquity than the 

 secondary deposits scattered here and there, it would not there- 

 fore follow, that the lignite which is found in its neighbourhood 

 must be regarded as a constituent part of this formation, and the 

 more so, since the clay-beds which contain it cannot be so con- 

 sidered. They simply fill a depression in its neighbourhood, and 

 we can merely conclude from the nature of the materials used in 

 filling it as to their age, since not even the perfect absence of 

 the characteristic blocks of granite clearly proves, that their ori- 

 gin is not referable to the diluvial formation. Since the smell 

 of amber now and then exhibited by a piece of wood from these 

 beds is considered as an insufficient proof that the mass of 

 vegetable remains which occur there belongs to the amber flora, 

 it seems difficult to discover any other proof. The change of 

 vegetable fibre however by nitro-sulphuric acid into an explosive 

 substance shows its possibility. A piece of this wood which exhi- 

 bited no smell of amber was subjected to this treatment, and 

 though it gave no useful explosive matter, it yielded as a secon- 

 dary substance a sort of resin which reminded one strongly of 

 the artificial musk produced from amber by nitric acid. In 

 consequence of this observation, I induced Dr. Reich to sub- 

 mit a number of fragments of wood from the locality above-men- 

 tioned, which seemed to belong to different Conifer?e, to exami- 

 nation, with a view to ascertain whether they contained any suc- 

 cinic acid : the results surpassed all expectation. Of fourteen 

 specimens, thirteen exhibited beyond all doubt the presence of 

 this acid, which may reasonably be assumed as coming from the 

 resinous constituents of the wood ; the fourteenth, which belonged 

 to Taxites Aykii, gave a crystallizable acid different from the 

 other, which unhappily, by reason of the very small quantity of 

 the wood examined, would not admit of further investigation. 

 But not only these fragments of wood showed in this way their 

 relation with amber, but the remains of fossil cones from the same 

 beds gave a similar result, amongst which indeed no particular 

 selection could be made, but they exhibited on the most careful 

 trial no smell of amber. They, as well as the lignite which did not 

 exhibit the well-known structure of the wood of conifers, yielded 

 on destructive destination fluids, in which the presence of cry- 

 stalline succinic acid could be ascertained by the microscope 

 and by chemical reagents. If then the occurrence of succinic 

 acid except from amber is so problematical, that amber may 

 be considered as its only source, we must admit also that coni- 

 ferous woods which contain it belonged not only to the arabei* 



