FOSSIL FOOD 281 



places where the salt was manufactured came to be known as 

 wych -houses. Droitwich, for example, was originally such 

 a wich, where the droits or dues on salt were paid at the time 

 when William the Conqueror's commissioners drew up their 

 great survey for Domesday Book. But the good, easy-going 

 mediaeval people who gave these quaint names to the inland 

 wiches had probably no idea that they were really and truly 

 dried-up bays, and that the salt they mined from their pits 

 was genuine ancient bay-salt, the deposit of an old inland 

 sea, evaporated by slow degrees a countless number of ages 

 since, exactly as the Dead Sea and the Great Salt Lake are 

 getting evaporated in our own time. 



Such, nevertheless, is actually the case. A good-sized 

 Caspian used to spread across the centre of England and 

 north of Ireland in triassic times, bounded here and there, 

 as well as Dr. Hull can make out, by the Welsh Mountains, 

 the Cheviots, and the Donegal Hills, and with the Peak of 

 Derbyshire and the Isle of Man standing out as separate 

 islands from its blue expanse. (We will beg the question 

 that the English seas were then blue. They are certainly 

 marked so in a very fine cerulean tint on Dr. Hull's map 

 of Triassic Britain.) Slowly, like most other inland seas, 

 this early British Caspian began to lose weight and to 

 shrivel away to ever smaller dimensions. In Devonshire, 

 where it appears to have first dried up, we get no salt, but 

 only red marl, with here and there a cubical cast, filling a 

 hole once occupied by rock-salt, though the percolation of 

 the rain has long since melted out that very soluble sub- 

 stance, and replaced it by a mere mould in the character- 

 istic square shape of salt crystals. But Worcestershire and 

 Cheshire were the seat of the inland sea when it had con- 

 tracted to the dimensions of a mere salt lake, and begun to 

 throw down its dissolved saline materials. One of the 

 Cheshire beds is sometimes a hundred feet thick of almost 



