of Siliceous Stalactites. 309 



.Allan, in his distress, seeking shelter under the mantle of 

 Werner ! He will find it in this case, however, but a cob- 

 web. Let us suppose, with Mr Allan, that the pupils of the 

 Freyberg school can view these anomalies in trap rocks, and, 

 in spite of such testimony to the contrary, continue to believe 

 in their igneous origin, it remains to be asked, what explana- 

 tion of these anomalies can be given to one, who is not a pupil 

 of the Freyberg school, and who does not admit the igneous 

 formation of trap rocks ? Can it be any thing but a confes- 

 sion, that the hypothesis is opposed by the phenomena ? 



Flinty matter sometimes occurs in older limestones than the 

 chalk, in such situations as to offer equally formidable objec- 

 tions to the igneous geologists. The specimens now exhibit- 

 ed to the Society seem to be of this description. They were 

 found, many years ago, in a quarry on the estate of Kirkton, 

 near Bathgate, West Lothian. This quarry was opened in a 

 bed of limestone, which dips under the great bed of limestone 

 belonging to the coal-field which extends north towards Lin- 

 lithgow. This great bed is regularly stratified, and dips to 

 the west at an angle of about 20°. It encloses the remains of 

 those marine animals which are common in the limestones of 

 the coal formation, with the beds of which, on both sides, this 

 mass is conformable. Flinty matter occurs in this bed, dis- 

 seminated in irregular thin layers, or in shapeless masses, oc- 

 casionally containing relics of marine animals. 



The bed of limestone to which we more particularly refer 

 exhibited in some places the ordinary massive or compact 

 structure, but in others it displayed that subconcentric la- 

 mellar concretionary arrangement so characteristic of calcedony. 

 The different layers of these undulating plates presented 

 many varieties of the botryoidal and mammillary forms. But 

 the layers did not consist exclusively of carbonate of lime. 

 Plates of flint likewise occurred, alternating with the lime- 

 stone in parallel layers. The siliceous matter likewise abounds 

 in the layers of limestone. When a mass of this substance 

 is exposed to the weather, the calcareous matter wastes, and 

 the flinty portion appears in high relief. Maceration in acid, 

 as has taken place in one specimen, likewise exhibits its true 

 structure. In the cavities produced by the irregular tui'i- 



