PROFESSOR HEDDLE ON THE MINERALOGY OF SCOTLAND. 103 
1° 301 grammes yielded— 
Silica, ; F “74 
From Alumina, . °011 
“Fol = 57 * 725 
Alumina, . : . ; oe 
Ferric Oxide, . ; a OAT 
Ferrous Oxide, , = coe FAG 
Manganous Oxide, . ‘076 
Lime, ; ; . : * 602 
Magnesia, ; ; . 38° 843 
Potash, . : 5 & bol 
Soda, : : ‘ J * 423 
Water, . : F LON 778 
100 * 204 
Loses 5°99 of the above water at 212°. Was very slightly acted upon by acids. 
I believe that the green “skin” of agates will prove to be celadonite, and 
not Delessite, as has been generally supposed. 
3. Found in the railway cutting about 400 yards west of Tayport, Fife. 
| It usually fills small druses of about an inch in size, in porphyritic amygda- 
| loid. Its colour there is a bright light apple-green ; it is opaque, dull, and its 
| structure is granular under the lens. Its specific gravity is 2 * 59. 
| Occasionally the mineral only coats the druse in mammillated layers. It then 
| somewhat resembles malachite, having lighter and darker bands of colour. The 
| interior of these druses is filled with the saponite, of which an analysis is given. 
| The saponite has a colour and structure markedly different from that of the 
' celadonite. Its colour is much duller than that of the celadonite, and slightly 
| dashed with brown ; it has a greasy or waxy lustre, and is semitransparent, 
| while the celadonite is quite opaque. There is no passage of the one mineral 
| into the other, and their line of junction is quite sharp. 
1°35 grammes yielded— 
Silica, ‘ : * 674 
From Alumina, . = (nt 
°685 = ba 692 
Alumina, . 5-786 
Ferric Oxide, 9° 752 
Ferrous Oxide, . ; Uae ach 
Manganous Oxide, . 307 
Lime, ‘ ‘ , oe weeeGS 
Magnesia, : 2958" 838 
Rotasin : ; 6 22 
Soda, ’ : ‘ : * 388 
Water, . : : . 10" 485 
100: 689 
Loses 5° 048 of the water at 212°. Is insoluble in acids. 
VOL. XXIX, PART I. 2) 
