Geological Society. 497 
of the water, and the quarter towards which the animals were 
passing ; the latter is indicated by the direction of the footsteps which 
form their tracks; the size and curvatures of the ripple-marks on 
the sand, now converted to sandstone, show the depth and direction 
of the current; the oblique impressions of the rain drops register 
the point from which the wind was blowing, at or about the time 
when the animals were passing. 
Demonstrations founded solely upon this kind of circumstantial 
evidence were duly appreciated, and are well exemplified, by the 
acute author of the story of Zadig ; who from marks he had noticed 
on the sand, of its long ears, and teats, and tail, and from irregular im- 
pressions of the feet, declared the size and sex, recent parturition and 
lameness of a bitch he had never seen; and who from the sweeping of 
the sand, and marks of horse-shoe nails, and a streak of silver on a 
pebble that lay at the bottom of a single footstep, and of gold upon 
a rock against which the animal had struck its bridle, inferred that 
a horse, of whose existence he had no other evidence, had recently 
passed along the shore, having a long switch tail, and shod with 
silver, with one nail wanting upon one shoe, and having a bridle 
studded with gold of twenty carats value. 
March 25.—A paper was first read “ On the Age of the Lime- 
stones of South Devon ;” by W. Lonsdale, F.G.S. 
The object of this communication is to show the nature and limits 
of the author's claim to having been the first to infer from zoological 
evidence that the limestones of South Devon would prove to be of the 
age of the old red sandstone; and it was drawn up at the request of 
Mr. Murchison, in consequence of the subsequent adoption and ex- 
tension of the proposed classification by Professor Sedgwick and 
that gentleman; and at the request likewise of Dr. Fitton, in conse- 
quence of the same views having been applied to some of the in- 
fra-carboniferous formations of Belgium and the Boulonnais. The 
paper commences with a summary of the opinions previously enter- 
tained respecting the age of the limestones. The authors quoted are, 
Woodward, 1722; Da Costa, Maton, Playfair, Berger, L. A. Necker, 
De Lue, T. Thomson, Kidd, W. Smith, Brande, W. Phillips, Hennah, 
Greenough, Sedgwick, W. Conybeare, J. J. Conybeare, Buckland, 
Dufrénoy, Elie de Beaumont, De la Beche, Prideaux, Boase, J. 
Phillips, Austen, Murchison, Bakewell and J. de Carle Sowerby. 
_ By these geologists the limestones are placed in the primary, trans- 
ition or graywacke and carboniferous series; Mr. Prideaux being 
the only author who ascribes them in part, and on mineral characters, 
to the old red sandstone; and Mr. J. Phillips, in his article on geo- 
logy in the Encyclopedia Metropolitana, hesitating to place them 
in a definite position, in consequence of the resemblance of many of 
the shells to species found in the mountain limestone, Mr, De la 
Beche, in his memoir on Tor and Babacomb Bays, also states that 
the limestones of that district rest on old red sandstone; and in his 
Report on Cornwall and Devonshire (1839), he says, “ that those 
who rely very exclusively on the character of organic remains would 
Ann. & Mag. N. Hist. Vol. vi. Suppl. 2K 
