Intelligence and Miscellaneous Articles. 71 



it from the Silurian plain of Nashville. The table-land is about 40 

 miles wide, and is intersected by the valley of the Sequachee River, 

 running iu a north-easterly direction along a subsidiary anticline from 

 near Jasper for a distance o£ sixty miles. 



From the base of the Cambrian beds, the whole Lower and Upper 

 Palaeozoic formations succeed each other in apparently conformable 

 sequence, except at the junction of the Upper and Lower Silu- 

 rian series, where a probable discordance occurs. The prolonged 

 period of subsidence and deposition at length gave way to elevation ; 

 acting with the greatest effect along the Alleghanies. Under these 

 circumstances, denudation preceded most rapidly along the tract 

 bordering the Protaxis, whilst the synclines were protected from 

 erosion to a greater degree ; and as the elevatory movement was 

 more rapid along the Unaka range, the flow of the streams was 

 generally westward. At a later period the Cumberland plateau 

 began to be formed by backward erosion of the strata in the 

 direction of the dip ; so that it owes its development to the erosion 

 of the Tennessee and Clinch rivers on the one hand, and to the 

 Cumberland river on the other. Where the Tennessee Eiver flows in a 

 north-westerly direction through the Cumberland plateau, the divide 

 between it and the Gulf of Mexico is only 280 feet above the river- 

 bed, whilst the table-land is 1400-1500 feet above. The author 

 infers, therefore, that when the river began to erode its channel the 

 plateau was relatively lower than the tract to the south of the 

 present course of the stream, but that by denudation the relations 

 have been reversed, whilst the river has never left its originally 

 selected course. 



The author compares the state of things with that which must 

 have occurred in the case of the northerly rivers running from the 

 centre of the Wealden axis ; but mentions that Prof. Safford and 

 Mr. J. Leslie account for the Cumberland plateau by faulting, though 

 he thinks that the well-defined escarpment along the valley of East 

 Tennessee seems to show that this cause is insufficient. 



In conclusion, he believes that the denudation was accelerated 

 during the pluvial or " Champlain " period, and calls attention to 

 the " Columbia formation " of the east side of the Alleghanies, and 

 to the deposit of red loam by which the surface of the country of the 

 valleys of the Tennessee and Sequachee is overspread, and which is 

 probably referable to a similar stage. 



3. " On certain Ornithosaurian and Dinosaurian Remains." By 

 R. Lydekker, Esq., B.A., F.G.S. 



VIII. Intelligence and Miscellaneous Articles. 



EXPERIMENTAL INVESTIGATIONS ON THOMSON'S LAW OF 

 WAVE-MOTION ON WATER. BY O. RIESS. 



<HE influence of surface-tension on the wave-motion of water 

 was, as is well known, first theoretically investigated by Sir W. 



