24 SMITHSONIAN INSTITUTION 



Proceeding southward through the cathedral town of Exeter, on 

 the Exe River, Lyme Regis, the well-known Mesozoic fossil locality 

 along the sea coast celebrated for its ichthyosaur remains, was briefly 

 studied (fig. 19). Next, the city of Bath, the fashionable watering 

 place located around the old Roman baths and in the center of the 

 Jurassic oolitic limestone outcrops, was of especial interest. Here the 

 houses built of white limestone and rising in successive terraces 

 present a more striking and handsome appearance than in perhaps any 

 other English town. Farther east, Salisbury Plain with its underlying 

 chalk formation afforded numerous outcrops, although again fossils 

 are not abundant. On the Plain, Stonehenge, the best-known example 

 of the ancient builders' craft in Great Britain, erected by a race of 

 Bronze Age people about 1500 B.C., is an object of much interest. 

 Located just northwest of Salisbury with its dominant feature, the 

 famous cathedral founded early in the thirteenth century, this more 

 ancient temple was undoubtedly devoted to sun worship, since on the 

 summer solstice the rising sun casts a shadow of the heel stone on the 

 altar. The geologist found in tracing the origin of the stones, that the 

 outer circle at Stonehenge (fig. 20) is made of blocks of Tertiary 

 sandstone which once covered the Plain, while the inner circle and 

 horseshoe are of igneous rocks which must have been brought from 

 South Wales, 200 miles away. 



South and east of London the chalk formation again comes to the 

 surface with frequent outcrops for collecting, in the anticlinal uplift 

 forming the Weald, bordered on the north and south by the Downs 

 with their ever-present flocks of sheep. Eastward along the Weald 

 the best exposures of the fossiliferous chalk beds and associated 

 greensands are along the sea coast, where at Dover and Folkstone the 

 geologist has ample opportunity for study (fig. 21). Return to 

 London was made through the hop fields of Kent, where in September 

 great numbers of pickers are busy. Here the London Basin with its 

 Tertiary sediments affords outcrops of the more recent rocks of 

 England. In a short time, therefore, one can review the entire geo- 

 logical column, by starting with the oldest igneous rocks in Cornwall, 

 continuing with the lower and middle Paleozoic sandstones and shales 

 in Devon, the upper Paleozoic limestone in Somerset and Gloucester, 

 followed by the Mesozoic oolites and chalk beds from thence eastward 

 through Canterbury to Dover, and ending with the Cenozoic clays and 

 sands in the environs of London. Although invertebrate fossils 

 needed to fill certain gaps in the study series were collected, the 

 information obtained for more accurate labeling and for present 

 studies was the most valuable result of this trip. 



