CONTENTS. 



2. Astronomy, 



Page Page 



On spots in the Sun, Ste. Gray 78 Obs. of a Solar Eclipse, Flamsteed 294 



On the same, by Mr. Derham 79 Observ. of the same, J. Chr. Facio 296 



A Meridian Instrument, Mr. Derham 129 On the same. Dr. Joh Ja. Scheuchzer .... 298 



Observ. of a Lunar Eclipse, Ja. Hodgson . . 134 On a Comet at Rome, John Ray 333 



On Solar and Lunar Eclipses, T. Brattle . . 148 On a Lunar Eclipse, Ja. and Jo. Scheuchzer 350 



OnCassini's Orbit of the Planets, Da. Gregory 152 On the same, by Tho. Brattle 379 



On tlie Solar Spots, Capt. Stannyan \66 On some Eclipses, Wm. Derham 485 



Astronomy of Comets, Edm. Halley 201 On a Lunar Eclipse, H. Cressener 548 



On finding Easter Day, &c. R. Thoresby . . 202 On the Solar Spots, Wm. Derham 622 



Rule for folding Easter, J. Jackman 250 On a Lunar Eclipse, by the same 700 



3. Mechanics. 



Motion of Pendulums, "Wm. Derham 172 Descent of Dust in Vacuo, by the same . . 208 



Resilition of Bodies, F. Hauksbee 208 



4. Hydrostatics. 



Weight of Air to Water, F. Hauksbee. .. . 288 Diff. Weights of Water, &c. the same 470 



Ascent of Water in Tubes, the same .... 289 Specific Gravity of Bodies, ditto 484 



Various Weights of Water, the same .... 453 Decrease of Space of Mixed Liquors, ditto 644 



Ascent of Water, by the same 464 Specific Gravity of Metals, ditto 698 



Diff. Density of Water by Heat, ditto 469 



5. Pneumatics. 



A New Baroscope, Mr. Caswell 120 Compressed Air on Hemisphere?, ditto .... 3S6 



Air from fired Gunpowder, Hauksbee .... 1 82 Air from Fired Gunpowder, ditto 363 



Quality of the same Air, ditto 183 Nature of the same Air, ditto 364 



Sound in Condensed Air, ditto 202 Density of Air in Heat and Cold, ditto 4l6 



Sound in Rarefied Air, ditto 203 Air Vitiated by Heat, ditto 6l3 



6. Acoiistics, Music. 



Sounds in Condensed Air, Hauksbee 202 The Motion of Sound, Wm. Derham 380 



in Rarefied Air, ditto 203 Nature, &c. of Sound, G. Grandi 471 



Theory of Music, &c. T. Salmon 243 No Sound through a Vacuum, Hauksbee . . 499 



On Deaf Persons Speaking, Rd. Waller . . . 378 Sound alters not its Direction, ditto 500 



Deafness cured by a Fever, Mr. Martin . . 379 On Sound through Water, ditto ibid 



7. Optics. 



Microscopical Observations, Sir C. H 29 On making Microscopes, Dr. Adams .... 551 



Spherico-Catoptric Theorem, H. Ditton . . 184 Refractions of Fluids, Hauksbee 616 



Expers. with a Burning Glass, Geoffroy . . 501 



8. Magnetism, Electricity. 



Magnetical Experiments, Derham .. 258, 259 Electricity of Glass, &c. Hauksbee 411 



Attrition m Vacuo, Hauksbee 270 of several Bodies, ditto 413 



Light by Attrition, ditto 307 of Sealing Wax, ditto 452 



Electricity of Glass, &c. ditto 324, 344 Light, &c. from Pitch, ditto 509 



Light from Glass, &c. ditto 355 No light from Flowers of Sulphur, ditto . . 528 



Variation of the Needle, J. Maxwell 36 1 Force of the Loadstone, ditto 6^ 



Light of Amber, Diamonds, &c. Dr. Wall 408 



