1819.] Memoirs of the Wernerian Society, Vol. II. Part II. 66 
published some years ago in the Annals of Philosophy, be cor- 
rect, it will follow from it that most of the rocks supposed 
hitherto to be peculiar to the newest floetz trap formation, 
belong to the old red sandstone, and constitute subordinate beds 
init. ‘Thus if East Lothian consists of old red sandstone, the 
porphyry slate of North Berwick law, and Traprene law, and the 
floetz trap rocks of Dunbar, must constitute beds in the sand- 
stone. ‘This would probably be made out in a satisfactory 
manner by travelling along the south coast of the Frith of Forth 
from Prestonpans to Dunbar, as the rocks are exposed for the 
greatest part of that way. 
III. Description and Analysis of a Specimen of Native Iron 
found at Leadhills. By Mr. H. M. Dacosta, M.W.S.—The 
specimen was found associated with galena, and was discovered 
by the workmen from its resisting the blows of a hammer. It 
possessed the external characters of iron, and was found com- 
posed of 
Aporad ceoas aghl.). daasieivome. 16°5 
RUC ania oacehahel ineraaia a oidheat. oh 
Loss, chiefly sulphir........ 0°5 
18-0 
IV. Mineralogical Observations in Galloway. By Dr. Grier- 
son.—There are three different granite districts in Galloway. 
Dr. Grierson formerly gave an account of the middle, or Dee 
district, in a paper published in a former volume of the Annals 
of Philosophy. The object of this paper is to give an account 
of the western, or Doon granite district. This district lies 
between Loch Doon and Loch Dee, and probably extends eight 
miles in length and four miles in breadth. Itis covered on all sides 
By arock, to which the author has given the name of compact gneiss. 
his gneiss rock can be traced sometimes for a mile, and some- 
times only for a few hundred yards. Greywacke always covers 
it; at least, Dr. Grierson no where found the greywacke 
in contact with the granite. Fragments of the gneiss are 
frequently met with in the granite. It contains likewise nume- 
rous beds of felspar porphyry. 
V.*Lithological Observations on the Vicinity of Loch Lomond. 
By Dr. Macknight.—The rocks round Loch Lomond are mica 
slate, which continues to Ben Lomond, which is itself composed 
of it. The mica slate contains thick beds of felspar porphyry 
and greenstone. Immediately to the south of Ben Lomond, the 
clay slate rocks commence. At Luss and Camstradden, they 
are quarried for roofing slate. The clay slate is followed by 
reywacke and greywacke slate, and these transition rocks are 
ollowed by the old red sandstone. 
I had an opportunity last autumn of examining a small portion 
Vou. XIII. N° I. E 
