NOTES AND QUERIES. 



39 



Fragment of " Slickenside, " exMbiting 

 two sets of sti'ia3 (nill size). 



arranged more or less at right angles to eacli other, and closely adhering, one 

 set being parallel, or nearly so, to the dip, and the other to the strike 

 of the beds. 



From this it vroM appear that the 

 beds above and below had two distinct 

 motions given to them, bnt at different 

 intervals of time. In the example be- 

 fore us we have evidence for believing 

 that at first one set of beds moved while 

 the other remained stationary ; and that 

 one half of the crushed intervening sub- 

 stance, while adhering to the moving 

 mass by cohesion was pulled into a state 

 of striation to the amount of only one- 

 half its thickness. The motion then 

 suddenly ceased, and the adjoining beds 

 were moved, but in a dii'ection directly 

 contrary to the first. The remauiing 

 portion of the pulverized material fol- 

 lowed this second impulse, and assumed 

 a striated structure, the lines of which 

 were parallel with the direction of the 

 displacement and consequently at an 

 opposite angle witli that which was first 

 formed. 



We have in Brockedon's patent pen- 

 cils a familar example of the recon- 

 solidation of a powdered substance by 

 the application of enormous pressui-e 



into a material harder and more free from grit, or otlier impurities, than the 

 original native plumbago, and to this our slickensides bear a striking analogy. 

 Dear sir, faithfully youi's, Geo. Y. Du Isoyee, M.li.I.A., Geological Survey of 

 Ireland. 



Published AccorxTS or Tossil Human Reimaixs. — Sir, — WiU you 

 oblige me by answering the following query in the " Geologist." I ask as 

 well for others as myself. Where may be procured the fullest and most re- 

 liable information respecting fossil human remains that have been discovered in 

 the world ? Subscriber, Redlands. — There is no coimected account of the 

 human remains discovered in various parts of the globe, and it is one of the 

 objects of the papers on the "Eust Traces of Man on the Globe." now pub- 

 lishuig in this magazine, to give a collected account of aU the reliable cases, 

 and to give illustrations of the ancient flint-weapons, etc., as also of the 

 stone-implements recently, or still in use amongst savage tribes in various parts 

 of the world. 



The best account of human remains published up to the present time will be 

 fomid in the appendix to M. Boucher de Perthes' book. Other notices may be 

 profitably consulted, such as Dr. Mantell's paper, read at the Oxford meeting 

 of the Ai'chseological Institute, 1850, and M. Marcelde Serres' several papers 

 in the Bulletin Soc. Geol. de Prance, Comptes Rendus, etc. 



Deposition of Warp. — Sir, — In " Notes and Queries," in the " Geolo- 

 gist" for December last, W. Nottingham asks two questions, viz., 1st. "V-VTiere 

 does the warp come from ? 2nd., How is it that the Humber and its tributaries 

 — the Trent, Ouse, Don, etc., are the only rivers in Great Britain that deposit 

 " warp" ? 



When we take into consideration the fact that the Plumber receives the 



