INDEX. 
material bear to the ordinary Orthoclastic Substance ? 
226. Knitted Structure, p. 229. Albite from Granitic 
Dykes in Hornblendic Gneiss, 235. From Exfiltration 
Veins in Syenitic Granite, 236. From Serpentinous 
and Talcose Rocks, 237. From Hornblendic and Chlo- 
ritie Rocks, 239. Oligoclase from Veins in Hornblendic 
Gneiss, 240. From Hornblendic Slate, 241. From 
Exfiltration Veins in Grey Granite, 243-245. From 
Bedded Porphyry, 245. Andesine from Granular 
Limestone in Micaceous Gneiss, 246. From Limestone 
Quarries, 247. From Diabase, near Limestone, 249. 
Labradorite from Gneissose and Serpentinous Rocks, 
251. From Hyperitic Diabase, 253. From Loch 
Scavaig, 253. From Diorite, 254. From Gabbro, 254. 
From Micaceous Gneiss, 256. From Porphyrite, 257. 
Anorthite from Anorthic Diorite, 260. From Gabbro, 
261. From Granular Limestone, 261. Latrobite, 
262. 
Chapter Third.—The Garnets.—Lime and Alumina Garnet, 
Colourless Garnet, Water Garnet, 299. Lime-Alumina 
Tron Carnet, Grossular, 299. Lime Iron-Alumina 
Garnet, Cinnamonstone, 300. Localities in which 
Garnets are found: Lower Limestone Beds, 308 ; 
Upper Limestone Beds, 308. Magnesia Iron-Alumina 
Garnet, Pyrope, 311. Iron-Alumina Garnet, Common 
Garnet from Gneiss, 312; from Mica Slate, 312; from 
Diorite, 313. Iron Garnet, Almandite, 314. Iron 
Manganese-Alumina, Iron Garnet, Precious Garnet, 
Manganesious Garnet, 315. 
Chapter Fourth.—Augite, Hornblende, and Serpentinous 
Change, 453.  Augite: Malacolite from Granular 
Limestone, 453. Malacolite from the vicinity of 
Serpentine, 458. Sahlite from Granular Limestone, 
458. Sahlite from Ben Chourn and from Tiree Marble, 
459. Sahlite from Hslie, 460. Coccolite from Gneissose 
Rocks, 462. Diallage from Metamorphic Rocks (Unst, 
Pinbain), 462, 463. Smaragditic Augite, 464. Augite 
from Diorite, 465. Augite from MHyperite, 467. 
Pseudo-Hypersthene from Hyperite, 478. Vitrified 
Augite—Augitic Glass, 481. Augitic Glass from 
Voleanic Rocks in Old Red Sandstone, 482. Con- 
version into Serpentine, 491, 501. Change by Hydra- 
tion ; Remoyal of Lime, of Silica ; Partial Peroxidation 
of the Iron Pseudo-Augite, 493. Total Peroxidation, 
but no removal of the Iron, 494. Change by Hydra- 
tion, Removal of the Silica, of the Iron, of most of the 
Lime, with augmentation of the Magnesia, 497. 
Schiller Spar, 499. Hornblende or Amphibole: Ami- 
anthus, Flexible Asbestus, 502. Asbestus from Granular 
Limestone, 503. Asbestus from Serpentine, 503. 
Antigoritic Allomorph-Nephrite, 504. Schistose Allo- 
morph, 505. Tremolite, 506. Actynolite from Horn- 
blendic Gneiss, 508. Alwminous Amphiboles: Edenite, 
509. Pargosite, 510. Hornblende Proper from Dial- 
lage Rocks, 511; from Diorite, 512 ; from Gneiss, 521; 
and from Igneous Rocks, 522. Alteration Products of 
Hornblende: Incipient Incrementation of Water, 
Peroxidation of the Iron, Decrement of Lime, 525. 
Hydrous Anthophyllite; Hydrated Fasciculitic Edenite, 
885 
526. Hydrated Amianthus; Mountain Cork, 527, 
Mountain Leather, from Granular Limestone, 527; 
from Silurian Slates, 528; from Old Red Sandstone 
528 ; from Amygdaloid, 529. Incipient Passage into 
Serpentine Hydrous Asbestus-Picrolite, 530. Hydrous 
Anthophyllite, 531. Varying circumstances must vary 
the mode of degradation of a rock, 545. 
Home (Davin Mitne). Additional Memoir on the Parallel 
Roads of Lochaber, 93. I. Localities where Beds of 
Sand, Clay, and Gravel at high levels occur, 94. II. 
Localities where Lakes exist, dammed by Detritus, and 
shewing subsidence or disappearance, 95. III. Probable 
Position of the Blockages of the Lochaber Lakes, 96. 
IVY. Supposition that Glaciers may have been formed 
in Corry n’ Eoin and Loch Treig, 99. V. How the 
Detrital Blockages of Glen Gloy and Glen Spean were 
removed, 101. VI. Effect of the Removal of the Glen 

Spean Blockage, 102. VII. The Glacial Markings in 
Lochaber, and their bearing on the Parallel Roads’ 
Question, 104. VIII. Dr Tyndall’s Lecture, 109. 
IX. Dr Tyndall’s Glacier Views, 113. Appendix. 
Hornblende, 209, 241, 502, 525. Chapter Fourth of the 
Mineralogy of Scotland. See HEDDLE (Professor M. F.). 
Hydrate of Dimethyl-Thetine, 598. See Lerts (Dr E. A.). 
Hydrobromate of Dimethyl-Thetine, 573. Its Action on 
Ethylate of Sodium, Oxide of Copper, Oxide of Mereury, 
and Ammonia, 576. See Brown (Professor Crum). 
Action of Nitric Acid and Alcohol on this Hydro- 
bromate, 603, 604, 607. See Lerrs (Dr E. A.). 
Hydrocarbon Sulphides, 612. See Lurrs (Dr E. A.). 
Hydro-Chlorate of Dimethyl-Thetine, 579. See BRown (Pro- 
fessor CRUM). 
I 
Intersections of one or more closed plane Curves, 150-159. See 
Tart (Professor P. G.). 
Todacetic and Bromacetic Ethyl Ether, 618. 
(Dr E. A.). 
Tron, its Thermal and Electric Conductivity, 717. 
Tart (Professor). 
See LErts 
See 


J 
JENKIN (Professor FLEEMING). On the Application of Graphic 
Methods for the Determination of the Efficiency of 
Machinery, 1. Dynamic Frame of Machine, 1. Ele- 
ments of Machines, 2. Joints, 3. Definition of a 
Complete Machine, 5. Lines of Bearing Pressure, 5. 
Driving and Resisting Elements, 5. Link’s Dynamic 
Frame, 6. Example, 8. Modification of the Dynamic 
Frame Couples, 11. Assumption that the Links of a 
Frame lie in one Plane, 12. Simple and Compound 
Dynamic Frames, 13. Efficiency of Elements, 14. 
Simple Machines: Lever, 16; Wheel and Axle, 17; 
Inclined Plane, 18; The Hanging Pulley, 18; Ordi- 
nary Direct-acting Steam Engine, 19; Wedge, 21 ; 
Spur Wheels, 22; Rolling Contact, 23; Belt and 
Pulley, 24. Compound Machines, 25. Compound 
Machines with one common element, 26. Half 
