STEVENSON— INTERRELATIONS OF THE FOSSIL FUELS. 71 



sects, while among the higher animals which perished in the bog are 

 Rhinoceriis leptorhimis and Elcphas antiquns. 



Deicke**" looks upon the Swiss diluvial coal as a link between 

 peat and brown coal ; it passes over into both types. He discussed 

 only the Alorschwyl deposit as Heer had given details respecting 

 those at Utznach and Diirnten. The coal lies in diluvium, 40 to 50 

 feet above the ]\fiocene, is covered with drift-material, often 80 

 feet thick, and rests on ashen-gray shale or on a clayey sand con- 

 taining small pebbles. The lowest coal layer encloses very many 

 stems of trees, among which Scotch fir, red and white spruces, oaks, 

 birches and others can be identified. All had been broken off and 

 the fragments are from 8 to 12 feet long with, in some cases, a 

 diameter of 3 feet. Except wdiere the stumps are rooted, the stems 

 are prostrate and show very marked compression. Birches are much 

 flattened, the width of a stem being often 24 times its thickness. 

 Conifers are less compressed, the width being rarely more than 4 

 times the thickness. Above this layer is a clay-shale parting, one 

 foot thick, on which rests a coal composed chiefly of grasses and 

 mosses, but containing many birches, some Scotch firs and rare 

 spruces. In the clay shale and in the lower coal, Deicke found a 

 great quantity of cones of Scotch fir, red and white spruce, rare 

 cupulas of oak, seeds of various grasses and wings of insects. The 

 second bench of coal is succeeded by 4 feet of coaly shale, on which 

 is another coal bed, averaging 3 feet and broken by shaly partings. 

 The whole deposit thins away toward the borders. The coaly shale 

 has nests of Schieferkohle and shows erect stems which, though frac- 

 tured, are not compressed. Deicke recognizes Waldmoor conditions 

 here ; a forest was overwhelmed by mud, on which a Torfmoor 

 developed. The trees died and were blown over; cones of spruce 

 and fir remained in the mud and projected into the growing peat; 

 Scotch firs, birches and the rest grew on the peat and were destroyed, 

 wdien that material increased. Then came the influx of detritus and 

 the resulting compression. Wood comprises about one tenth of the 

 mass. When exposed to the air and sunshine, the lignite changes, 

 loses texture and becomes Pechkohle ; but complete change takes 



90 J. C. Deicke, " Ueber die Diluvial-Kohle bei Morschwyl im Kanton 

 St. Gallen," Ncucs Jalirbuch, 1858, pp. 659-663. 



