Freshwater Limestone in Forfarshire, ^c. 77 



It consists almost wholly of carbonate of lime ; is extremely hard and compact, 

 and when broken and viewed with a lens, is in parts decidedly crystalline. Its 

 fracture is fine-grained, slightly splintery, approaching to even when viewed 

 in the great, but uneven when viewed in the small. Many blocks of this sub- 

 stance, which have been exposed for several years, are found to have resisted 

 entirely the action of the frost and the weather. Some of these, which have 

 been built round the great spring, measure 2^ feet in length, and above 1 foot 

 in breadth and thickness. Some masses present a wavy mamillar surface, and 

 resemble stalagmite. Some few have a lamellar texture. 



The rock is traversed vertically by numerous irregular tubular cavities, the 

 sides of which are in general fretted with minute stems and fibres of fossilized 

 vegetables in a very friable state, apparently Charae. Since clusters of these 

 vegetables sometimes occupy the centres of the cavities, they possibly may 

 have occasioned the cavities themselves. I shall notice these cavities more 

 particularly in the sequel, when comparing the tufaceous limestone or rock- 

 marl of the Bakie with ancient freshwater limestone. The flattened concre- 

 tions of limestone sometimes consist almost entirely of aggregations of fos- 

 silized stems of Charae, and in respect of their general composition they do 

 not differ materially from the continuous stratum. 



Organic Remains of the Marl. 



Quadrupeds. — The remains of quadrupeds are frequently met with in the 

 shell-marl of this lake ; but in the tufaceous limestone or rock-marl I have not 

 yet discovered them. The present proprietor has shown me the horns of stags 

 and bulls of large size, taken out of the marl within his memory ; and in the 

 Statistical Account of Scotland, vol. ii. p. 213, the horns of a stag, weighing 

 24 pounds, and the tusk of a wild boar, are mentioned as having been found 

 in the Bakie and presented to the Society of Antiquaries. 



The remains of quadrupeds have also been found in the marl of the neigh- 

 bouring Loch of Kinnordy, and have been dredged up in some of the marl- 

 lochs that have not been drained, from the depth of 16 feet below the surface 

 of the water. 



It is by no means obvious in what manner these animals, which are active 

 in swimming, were lost in lakes of such moderate dimensions as those in ques- 

 tion, and became buried in the marl. Mr. Blackadder has suggested, with 

 great sopearance of probability, that they were drowned in passing over the 

 lake when frozen, at those points where, owing to the springs, the ice was 

 weakest, and where, as I have previously stated, the marl is produced in the 

 greatest quantity. He has remarked also, that in the winter the marshy borders 



