Part Iii.--Wonders of the Sky.

Chap. I. The Colour of the Sky 250

Chap. II. The Aurora Borealis 254

Chap. III. Parley tells of some other Meteors Parhelia or Mock Suns 263 Ignes Fatui 264 Experiment to show the cause 266

Chap. IV. Shooting Stars 267 What they are 269

Chap. V. Meteoric Stones, or Aerolites 273 How they are caused 277

Chap. VI. Bloody Rain 280 Red Snow 281 Showers of Frogs and Fish 282

Chap. VII. The Spectre of the Brocken 285

Chap. VIII. Some other instances of Aerial Reflection Souter Fell 291 What a Friend of Parley's saw 293 Dover Castle 293 What Humboldt saw 294 What Captain Scoresby saw 295 Apparent distance of Object 296

Chap. IX. Fata Morgana 299 The Mirage 299

Chap. X. How Parley supposes these appearances to be produced 303 Refraction 305 Reflection 311

Conclusion. Of some other Wonders, &c.