766 



EXPLANATION OF PLATES. 



Fig. 9. Julus, an exotic species, to shew the character 



of the genus. 

 Fig. 10. Scolopendra of that family with alternate 



joints. 

 Fig. 11. Py cnogonum Balamaru m . 

 Fig. 12. Aranea Parletina. 



PLATE CCXXII. 



Contains twenty-one Diagrams for illustrating the 

 Mathematical Theory of Crystals. 



PLATE CCXXIII. 



the 



Contains thirty-eight Diagrams for illustrating 

 Mathematical Theory of Crystals. 



Fig. 34. Represents the Goniometer used by Rome 

 de Lisle and Hauy for Measuring the Angles 

 of crystals. 



PLATE CCXXIV. 



Fig. 1. Represents the Reflective Goniometer invent- 

 ed by Dr Wollaston for Measuring the Angles 

 of Crystals. 



Fig. 2. Represents the Reflecting Goniometer invent- 

 ed by Dr Brewster. 



Fig. 3 — 25. Are Diagrams for illustrating the Mathe- 

 matical Theory of Crystals. 



PLATE CCXXV. 



Fig. 1 — 8. Are Diagrams for illustrating the Mathe- 

 matical Theory of Crystals. 



Fig. 9- Is the primitive form of Leucite or Amphi- 

 gene. 



Fig. 10. Analcime, or Cubizite. 



Fig. 11. Sulphate of Magnesia. 



Fig. 12. Vesuvian, or Idocrase. 



Fig. 13. Meionite. 



Fig. 14. Mesotype, or Radiated Zeoliie. 



Fig. 15. Id. 



Fig. 1 6. Chrysoberyl, or Cymophane. 



Fig. \7, 18. Chrysolite, or Peridot. 



Fig. 19. Stilbite, or Foliated Zeolite. 



Fig. 20. Prehnite. 



Fig. 21, Wolfram. 



Fig. 22. Sulphate of Barytes. 



Fig. 23. Sulphate of Strontian. 



Fig. 24. Granatite, or Staurptide. 



Fig. 25. Talc. 



Fig. 26. Arsenical Pyrites, or Mispickel. 



Fig. 27. Gypsum, or Sulphate of Lime. 



PLATE CCXXVI. 



Fig. 1, 2. Pistazite Epidote, or Zoisite. 



Fig. 3. Axinite, or Thummerstone. 



Fig. 4. Amphibole, Hornblende, Actinolyte, Gram- 



matite, and Tremolite. 

 Fig. 5. Augite or Pyroxene, Coccolite, Diopside, and 



Salite. 

 Fig. 6. Felspar. 

 Fig. 7. Cyanite, or Disthene. 

 F'g- 8, 9- Sulphate of Copper. 



Fig. 10. Carbonate of Lime, Equiaxe of Hauy. 



Fig. 11. Ditto, Inverse of Hauy. 



Fig. 12. Ditto, Metastatic of Hauy. 



Fig. 13. l>itto, Contrasting of Hauy. 



Fig. 14. Ditto, Regular Six-sided Prism. 



Fig. 15. Quartz. 



Fig. 16. Tourmaline, or Schorle. 



Fig. 17. Oligiste, or Glance Iron ore. 



Fig. 18. Apatite. 



Fig. 19. Nepheline, or Sommite. 



Fig. 20. Garnet. 



Fig. 21. Diamond. 



Fig. 22. Topaz. 



Fig. 23. Calamine. 



Fig. 24, 25. Zircon. 



Fig. 26. Harmotome, Cross stone, or Staurolite. 



Fig. 27, 28. Molybdate of Lead. 



Fig. 29. Common form of Anatose, or Octahedrite. 



Fig. 30. Primitive form of Carbonate of Soda. 



Fig. 31. Common form of Carbonate of Soda. 



PLATE CCXXVI I. 



Fig. 1. Is a perspective representation of a Draw- 

 «• loom, adapted for Damask Tweeling. 



Fig. 2 — 16. Are various Diagrams for illustrating the 

 Theory of Curve Lines and Surfaces. 



PLATE CCXXVIIL 



Fig. 1 



Is the representation of an Ancient Dial found 

 in 1741, in the Ruins of a Roman House in 

 Tusculum, and supposed to have belonged to 

 Cicero. 



Fig. 2. Is a very curious Portable and Ancient Dial, 

 dug out of the ruins of Portici in 1755. 



Fig. 3. Is a Diagram for illustrating the general prin- 

 ciples of Dialling. 



Fig. 4 and 5. Shew the method of Tracing a Meri- 

 dian Line from Three Shadows of a Stile. 



Fig. 6. Shews the method of transferring the Meri- 

 dian Line to any place. 



Fig. 7. Represents an Universal Equinoctial Dial. 



Fig. 8. Is a perspective representation of an Horizon- 

 tal Dial. 



Fig. 9. Shews the method of constructing a Horizon- 

 tal Dial. 



Fig. 10. and 11. Shew a geometrical method of con- 

 structing Horizontal Dials. 



Fig. 12. Illustrates another geometrical method of 

 constructing Horizontal Dials. 



Fig. 13. Shews the method of constructing Dialling 

 Scales. 



Fig. 14. Shews the method of constructing Horizon- 

 tal Dials by Dialling Scales. 



Fig. 1 5. Points out the method of constructing Hori- 

 zontal Dials, by means of a Globe. 



Fig. 16. Is a Vertical South Dial. 



Fig. 17. Is a Vertical North Dial. 



Fig- 18. Diagram for explaining the nature of Verti- 

 cal East and West Dials. 



PLATE CCXXIX. 



Fig. 1 . Represents an East Dial. 

 Fig. 2. Represents a West Dial. 



