A HISTORY OF SUSSEX 



numerous fish, and a fine series of plants, which last have been care- 

 fully studied by Mr. Seward/ These plants consist of ferns, cycads and 

 conifers of Jurassic types, but include none of the higher flowering plants 

 which mark, the incoming of the Lower Cretaceous period abroad. 

 Whilst recognizing the strikingly Jurassic appearance of the Wealden 

 animals and plants, it should not be forgotten however that truly marine 

 fossils, on which our geological classification is mainly based, are practi- 

 cally unknown in the Wealden strata. Until its marine fauna is better 

 known the exact relation of the Wealden to the Upper Jurassic and 

 Lower Cretaceous of other regions must remain somewhat doubtful. 



The absence of lime and of certain compounds necessary for plant 

 life, as well as the common occurrence of poisonous iron salts, make most 

 of the country occupied by Wealden strata very infertile and more fitted 

 for oak forest or permanent pasture than for tillage. Where orchards or 

 fruit or hop-gardens thrive it will generally be found that the underlying 

 strata are buried under several feet of superficial ' Drift,' which quite 

 alters the character of the soil. The Hastings Sands form undulating 

 country with steeper slopes than those of the Weald Clay, the beds of 

 sand forming ridges roughly parallel to the folds with east and west axis, 

 which are so marked a feature in Sussex geology. They rise in places 

 to considerable heights, as will be seen on comparing the geological 

 with the orographic map. 



There is one important product of the Wealden strata that should 

 be mentioned, though it will again be referred to in a later volume in the 

 section on ironworks of the Weald. For many centuries the Weald 

 was one of the most important iron-producing districts of Britain, the 

 ore commonly used being the clay-ironstone nodules at the base of the 

 Wadhurst Clay. These were dug in bell-pits of no great depth, and 

 worked with oak charcoal, which yielded steely wrought-iron of excellent 

 quality. Later on a considerable quantity of cast-iron was made ; but 

 the industry was finally abandoned in the early part of the nineteenth 

 century, owing to the growing scarcity of charcoal and the gradual 

 introduction of coal and of the associated Coal Measure ironstone." 



There is another product of the Wealden strata that deserves 

 mention. Two borings for water at Waldron, the one at Heathfield 

 railway station, the other at New Heathfield Hotel, struck inflammable 

 gas in the Fairlight Clay.^ This gas seems, according to the analysis by 

 Mr. S. A. Woodhead, to be a genuine petroleum derivative, containing 

 72 per cent of marsh gas, mixed with enough oxygen (18 per cent) to 

 make it slightly explosive. The gas has been used for lighting the rail- 

 way station and offices. 



As the main dome of the Wealden anticline causes the strata in 

 Sussex to have a general dip to the south, if we leave out the minor 



I Catalogue of the Mcsozoic Plants in the Department of Geology, British Museum ; The It'cMen Flora 

 (8vo). 



a W. Topley, 'Geology of the Weald,' chap. xix. (1875). 



3 C. Dawson, ' On the Discovery of Natural Gas in East Sussex,' Quart. Jouni. Gecl. Soc. liv. 

 564-7 1 (1898). 



6 



