
_ PROFESSOR HEDDLE ON THE MINERALOGY OF SCOTLAND. .. _ 247 
usually plicated bed of granular limestone, so convoluted and fractured, and 
cut up by dykes, that it is difficult to determine whether there be not a greater 
’ number of beds than one. 
The lime is best seen about a mile to the mort of Milltown. It has been 
quarried here and there, where anticlines brought it to the surface. In one 
of these openings, a large mass of a substance simulating tremolite in 
form, but quite distinct in composition, was found; and among the crystals of — 
this substance a single crystal of andesine was also found. 
This crystal, which was from the centre of the mass, was perfectly fresh and 
- unaltered. It was over an inch in every direction, had distinct strice, was 
moderately lustrous and somewhat translucent, of a pale-blue colour, a cleavage 
angle about 86° 28’ or 30’, and specific gravity 2° 672. 
~The only substances immediately associated with it were the new mineral, 
calcite, and minute tufts of light green tremolite. In granitic veins in the 
vicinity there was an orthoclase of a dull-white colour, very similar in appear- 
ance to oligoclase, and Biotite. 
No impurity was visible in the portion analysed. 
1°3 grammes yielded—- 

Silica, : ee! 
From Alumina, e022 
oe = 58 + 384 
AVuminae 0): Te) I~ 22496 
Ferric Oxide, . ; 2 A Sais) 
Manganous Oxide, _, : vlse 
Magnesia, .._. 3 tr. 
‘Lime, 5 +341 
Potash, 3° 197 
Soda, 5: 209 
Water, © 3°409 
100°308 
Insoluble silica, : 527; possible impurity, tremolite. 
- 2and 3. From the Limestone Quarry at Delnabo, Glen Gairn, Aberdeenshire. 
The rock in the neighbourhood of this granular limestone is the ordinary 
Haughtonite gneiss of Aberdeenshire; where it approaches the lime it 
becomes very highly metamorphosed ; where in near contact with it, it is a 
nondescript mixture of a flakey biotitic gneiss, with a granular paste of coccolite. 
Imbedded partly in this singular compound, and partly in the lime, are 
numerous minerals, some more affecting the one, some the other; the less 
