66 Analyses of Books. {JAN. 
of the east bank of Loch Lomond, near Buchanan House, just 
where the greywacke terminates. The next rock is a limestone, 
which is probably transition, though it does not possess the usual 
characters of that kind of rock. The limestone is succeeded by 
a very coarse gravel stone, composed almost entirely of rounded 
quartz pebbles, seemingly cemented by a quartzy matter. This 
rock is obviously a modification of the old red sandstone, which 
a little to the south appears in its usual characters. This part of 
the Grampian agrees in its structure with every other cross 
section of these mountains. which I have had an opportunity of 
examining. 
VI. Description of Ravensheugh. By Dr. Macknight.—This 
is the name given to a point of the coast included in the Earl of 
Haddington’s pleasure-grounds at Tyningham, about six miles 
north-west of Dunbar. It consists of a set of beds forming a 
ock, which exposes a precipitous front to the sea, about 40 or 
50 feet in height. This rock is composed of floetz trap beds 
reposing on old red sandstone. The trap beds consist of basalt, 
red and green i tuff, impregnated with lime, clinkstone, and 
porphyry slate. The curious circumstance attending it is, that 
the beds of sandstone over which this floetz trap rock lies, seems 
to run beneath the basalt in every direction, assuming the form 
of a vast cup, or cavity, filled with the floetz trap. This depres- 
sion Dr. Macknight accounts for, by supposing that the Acatz 
trap was deposited upon the sandstone before this last rock was 
completely deposited. Hence it would, he thinks, squeeze down 
the sandstone, and cause the depression which exists. 
If this explanation be well founded, the specific gravity of the 
sandstone below the floetz trap would be greater than at a dis- 
tance from it. 
VII. Hints regarding the Coincidence which takes place in the 
Pressure 7, the Atmosphere at different Latitudes, and at nearl 
the same Time. By the Right Hon. Lord Gray, F.R.S. Lond. 
and Edin. &c.—His Lordship shows, by a set of curves, exhibit- 
ing the march of the barometer, during two years, at Gordon 
Castle, Kinfauns Castle, Greenwich Observatory, and Plymouth, 
that the rise and fall was nearly simultaneous at all these places. 
He thinks that this will hold nearly from the pole to the equator, 
and is exceedingly anxious to have the means of verifying his 
conjecture by observations made in the southern hemisphere. 
(To be continued. ) 
