Mr. Drew on the Succession of Beds in the Hastings Sand. 809 
come in contact with plutonic masses, they exhibit that highly 
erystalline aspect which induced Macculloch and others of the Scotch 
geologists to regard them as occupying an extremely low position 
among the sedimentary series, and to apply to them the Wernerian 
term “primitive.’”’ Many of Macculloch’s descriptions, however, 
show that this assumed low position is not the true place of this 
gneiss among the sedimentary rocks which make up the Highlands 
of Scotland. 
In a section from the southern flank of the Grampians to Loch 
Earn (and in other sections, from Loch Earn to Loch Tay, from 
Dunkeld to Blair Athol, in the Ben y Gloe Mountains, in Glen 
Shee, &c.), there is seen a sequence which indicates that this gneiss 
is the highest portion of the series of rocks, with underlying quartz- 
rock and limestone. 
In the county of Donegal, Ireland, a like sequence is seen. A 
section from Inishowen Head to Malin Head, along the east side of 
Loch Foyle, presents us with gneissose rocks above limestone and 
quartz-rocks, exactly as in Scotland. In no portion of Scotland 
south of the Caledonian Canal, nor in the North of Ireland, did the 
author recognize any trace of the ‘‘ fundamental gneiss.” 
March 6, 1861.—Leonard Horner, Esq., President, in the Chair. 
The following communications were read :— 
1. “On the Succession of Beds in the Hastings Sand in the 
Northern portion of the Wealden Area.” By F. Drew, Esq., F.G.S., 
of the Geological Survey of Great Britain. 
Having first referred to the division of the Wealden beds by former 
authors into the ‘‘ Weald Clay,” the ‘‘ Hastings Sand,” and the 
“Ashburnham Beds,” and the subdivision of the ‘‘ Hastings Sand” by 
Dr. Mantell into ‘‘ Horsted Sands,” ‘ Tilgate Beds,” and ‘* Worth 
Sands,” and having defined the district under notice as lying be- 
tween and in the neighbourhood of the towns of ‘Tenterden, Cran- 
brook, ‘Tunbridge, Tunbridge Wells, East Grinstead, and Horsham, 
Mr. Drew proceeded to describe, first, the several beds in the meri- 
dian and vicinity of Tunbridge Wells. ‘The Weald Clay is at least 
600 feet thick in this district, and is underlain by sands and sand- 
stones, termed by the author the ‘‘ Tunbridge Wells Sand,” on ac- 
count of its being well exposed there. ‘This subdivision is about 
180 feet thick, and was described in detail,—an important feature 
being the ‘ rock-sand,” or massive sandstone forming the picturesque 
natural rocks of the neighbourhood. ‘The shales and clays under- 
lying these sands form the ‘‘ Wadhurst Clay” of the author, and are 
at places 160 feet thick. ‘This subdivision has yielded much iron- 
stone in former times. It is underlain by other sand and sand- 
stones, more than 250 feet thick, also yielding ironstone. ‘These 
are termed ‘‘Ashdown Sand” by Mr. Drew on account of their 
forming the heights of Ashdown Forest. 
Eastward of the meridian of Tunbridge Wells Mr. Drew has found 
