CONTENTS. Ill 



Page Page 



Construction of the Heavens, Herschel 6 II, 680 Astronomical Observations, .... Zach .... 651 



On the Comet of 1783, E. Pigott . . 621 A New Variable Star, Goodricke 653 



A New Variable Star, E. Pigott . 649 



3. Gunnery, Projectiles. 

 Experiments on Gunpowder, . .Thompson 88 



4. Mechanics. 

 New Method of the Screw, . . Hunter ... 28 On the Friction of Bodies, .... Vince .... 654 



5. Pneumatics. 



Of a New Eudiometer, Cavendish 354 On Directing Air Balloons, .... Galvez . . . 625 



An Improved Air-Pump, Cavallo. . . . 453 



6. Optics. 



Micrometer for Angle of Posit. . Herschel . . 155 Great Powers of his Telescopes, Herschel . . 234 

 Refract, and Velocity of Light, P. Wilson. . 1 84 New Eye-glasses for Telescopes, Ramsden. . 350 

 New Lamp Micrometer, Herschel . 229 Light of Bodies in Combustion, G. Morgan 668 



7- Electricity, Magnetism, Thermometry. 



Heat of the Gulph Stream, . . . Blagden . . 115 A New Electrometer, Brook .... 308 



Exper. on Cold at Glasgow, .. P Wilson. . 129 Congelation of Mercury, . . . . Hutchins. . 411 



Thermometrical Experiments, Cavallo. ... 1 57 On the same subject, Cavendish 420 



An Improved Thermometer, . . Six 195 On the same, Blagden . . 431 



On very weak Electricity, .... Volta .... 263 Variation of Local Heat, Six 609 



Thermom. for Great Heat, Wedgewood 278, 57 1 Vacuum, Non-conducting, .... W. Morgan 699 



Class III. Natural History. 

 1. Zoology. 



On the Tyger Cat of the Cape, Forster. . . . 1 The Ophidium Barbarum, . . . . Broussonet 134 



Account of the Turkey, ...... Pennant . . 32 The Turnip Caterpillar, Marshall . . 386 



The Termites of Africa, &c. . . Smeathman 60 An undescribed Bird, Lightfoot . . 630 



The Gum Lacca Insect, Kerr 124 



1. Botany. 

 New Plant of the Fungi Order, Woodward 607 Bark Tree in St. Lucia, Davidson. . 619 



3. Mineralogy, Fossilogy, &c. 



On Scoria from Iron Work, . . .More .... 182 The Terra Ponderosa, &c Withering 544 



Rowley- rag and Toad-stone, . . Withering 290 On Mixing Gold with Tin, .... Alchorne. . 622 



Account of Ambergris, .... Schwediawer 3S9 On a Mountain in St Vincent's, Anderson 634 



Derbyshire Black Wadd, Wedgwood 409 Spec. Grav. at Dif. Temperatures, Kirwan 696 



Wells at Sheerness, Harwich, &c.Page .... i6l 



4. Geography and Topography. 

 The Ganges and Burrampooter, Rennell . . 39 



5. Hydrology. 

 Artificial Spring of Water, .... Darwin. . . 627 



