NATURE, CHARACTER, AND ADAPTABILITY OF FLINT. 205 



originally yellowish, it retains its colour more persistently. The dulness, also, of 

 a fresh fracture is changed for a more shiny surface, and under some circum- 

 stances, such as when alkaline water has affected the flint, the surface becomes 

 quite smooth and shining, showing the "patina" that may he recognized, for 

 instance, on the old flint implements from the gravel. 



The discoloration and " patina," as well as the " dendritic " markings of metallic 

 oxides creeping over parts of the surface, and incrustations of oxide of iron and of 

 carbonate of lime by permeating waters, cannot be taken as independent evidences 

 of very great age for worked flints, since these superficial changes and appear- 

 ances can be produced within limited periods of time ; nevertheless it is necessary 

 to notice them as the result of some lapse of time, and of certain conditions of 

 deposit, as well as indications sometimes not only of the differences of faces pro- 

 duced artificially from natural surfaces of the flint, but of the successive production 

 of artificial and accidental fractures in worked flints. 



P.S. The very many Memoirs and Books in which Flint Implements and the 

 methods of their manufacture have been treated of since 1860 constitute a litera- 

 ture of itself *. 



Besides the standard works on the subject by Nilsson (' On the Stone-Age ' &c. 

 1843-67), Stevens ('Elint Chips' &c. 1870), Evans ('Ancient Stone Implements' 

 &c. 1872), and the many papers and notices referred to by them, we must espe- 

 cially direct attention to Mr. S. J. Mackie's remarks on the manufacture of flint 

 tools, in the ' Geologist,' 1861, vol. iv. pp. 26-29, and to Professor T. M c Kenny 

 Hughes's paper on the same subject (Proc. Soc. Antiq. Lond. 2nd ser. vol. iv. p. 94), 

 part of which was afterwards published in extenso in the 'Geological and Nat. -Hist. 

 Repertory' &c., May 1, 1868, vol.ii. No.34, pp.126 &c., Mr.Mackie's further account 

 of "the natural fractures of flints," in vol. iii. pp. 205 &c., and Mr. T. Baines's 

 interesting and illustrated letter on the Australian flake-makers, ibid. pp. 258-262. 

 See also Professor T. M C K. Hughes's note on the fracture of chert and flint in the 

 ' Report Brit. Assoc.' for 1872, Trans. Sect. p. 189 ; and the late Mr. Henry Christy's 

 remarks on the subject, ' Transact. Ethnolog. Society,' New Series, vol. iii. 1865, 

 pp. 362 &c., and ' Eeliquia3 Aquitanicse,' Parts II. and III., 1866, pp. 13-20. 



T. R. J. 



September 1873. 



* Many references will be found in Mortillet, Trutat, and Cartailhac's ' Materiaux pour Phistoire de 

 1'Homme,' 1864-73. 



2 F 



