200 



1. When its thin edges are examined by a strong light, or when 

 very thin slices are inspected in the usual way, it is translucent, 

 transmitting a reddish-brown light, whereas coal is opaque on the 

 thinnest edges. 



2. Its fracture, though conchoidal, is perfectly dull in every 

 direction. 



3. Its streak is not shining, but quite dull. 



4. It changes colour strongly in the streak, which exhibits a dis- 

 tinct pale ochre yellow. 



5. It breaks with some difficulty, especially in the cross fracture, 

 and exhibits some degree of elasticity. It is, therefore, not brittle. 



6. It ignites very readily, and gives out much light ; but when 

 this expires, as it soon does, the remaining mass with great difficulty 

 affords the redness of ignition, as observed in coal under similar cir- 

 cumstances ; and it retains its form, though it becomes white by in- 

 cineration. 



It consists of volatile matter from 72'5 to 84-1 per cent. 

 White solid residue, 27-5 to 15-9 

 It affords a large quantity of fine combustible gas, and also, on dis- 

 tillation, yields much parajine. 



It occurs in a bed in the coal formation, associated with shale and 

 ironstone, in the county of Linlithgow, near Bathgate. 



The Central Board of Customs of the German Zollverein, assisted 

 by the principal mineralogists of Berlin, have, since this paper was 

 written, decided that the Linlithgowshire mineral is not a coal, and 

 may be imported duty-free, which coal is not. 



2. Notice of the Blind Animals which inhabit the Mammoth 

 Cave of Kentucky. By James Wilson, Esq. 



The author commenced with a general sketch of the natural 

 character and condition of the great cave, as it is the peculiarities of 

 their local position which constitute the most remarkable feature in 

 the history of the animals by which it is inhabited. The cave 

 liescends through the uppermost rocks of the " Barrens " to those 

 which are nearly or quite upon a level with the Ohio. Though 

 called a cave, it is in fact a series of underground galleries, branch- 

 ing from and inosculating with each other in various directions, the 



