GRAVESEND. 387 



hill just described, with its many strata, and which lies 

 higher than the surface of the hills near the chalk pit, 

 most certainly overlies the chalk, for visso star pa 

 krita. All the hill banks, strand backarna, of the 

 Thames, i-J- musket shot below this hill, consist of bare 

 chalk, either pure or mixed with Flints and small 

 Pebblestones.* 



Svin. To prevent these animals from grubbing up 

 the ground, and entering the ploughed fields through the 

 hedges, they were, in Kent and Essex, both ringed in the 

 snout and bore on their necks triangular wooden yokes, 

 exactly in the same way as is done with us here in 

 Sweden. 



Aim. Elm. When we were walking to-day down 

 by the banks of the river below Northfleet, Nordfleet, 

 where the river banks consist almost entirely of chalk, 

 with interbedded flints here and there, with soil, svart- 

 mylla, almost of a brick colour thereupon, we remarked 

 how the large Elms which grew in the hedges on the 

 river banks had penetrated with their roots through the 

 soil, which was here 2 feet thick or more, right down to 

 the chalk ; but as soon as they met the chalk they very 

 seldom entered it, but then began to run horizontally 

 along the bottom of the soil above the chalk. We re- 

 marked this of very many Elms. The chalk is probably 

 too hard for their roots. It was only in one single place 

 that I could see that a couple of Elm roots entered a 

 fissure in the chalk for a depth of 1 foot or 18 inches 



* The beds here described are now known as the Oldhaven Pebble Beds 

 of the Woolwich Series (Whitaker), and the Thanet Sand (Prestwich). This 

 section was cited by Sir Torbern Olaf Bergman, (?)'orig. work, German 

 tr. by L. H. Rohl in Welt-beschreibung, Th. I., cap. V., § 39., p. 114 

 Greifsvald, 1769-74, 8vo. And again transl. into German, incorrectly, by 

 Carl Abraham Gerhard, Vcrsuch einer Geschichte des Mineral-rekhs. 

 Berlin, 1781-2, 8vo. Erster Theil, $ 100, p. 190. [J. L.] 



2C 2 



