By the late eighteenth century, scientists had discovered certain types of gas, such as 'fixed air' (carbon dioxide), but their composition was little understood. Relatively few investigations into gases had taken place, and so the polymath Joseph Priestley (1733–1804) was able to make major breakthroughs in the field using a range of experimental techniques. While living near a brewery, he found that it was possible to outline the shape of the gas above fermenting beer with smoke, and that fire would burn with varying strength depending on the composition of the air. This three-volume collection first appeared between 1774 and 1777. Priestley acknowledges that Volume 3 (1777) would more greatly interest those with technical training in the physical sciences as compared with general scholars. It also highlights some new and important inferences, notably on the function of blood in respiration.

Table of Contents:
Preface; Introduction; 1. Of the production of dephlogisticated air from the several metals; 2. Of the phenomena which attend the solution of some of the semi-metals in spirit of nitre; 3. Of the production of dephlogisticated air from earthy substances; 4. An attempt to ascertain the quantity of spirit of nitre, in a given quantity of dephlogisticated air; 5. Observations on respiration, and the use of the blood; 6. Miscellaneous experiments and observations relating to dephlogisticated air; 7. Of the influence of oil of turpentine and spirit of wine on common air; 8. Miscellaneous experiments relating to common air; 9. Of the impregnation of water with nitrous air; 10. Of the absorption of nitrous air by oils, spirit of wine, and caustic alkali; 11. Of the phenomena attending the absorption of nitrous air by acid liquors; 12. Of the processes by which nitrous air is brought into a state in which a candle will burn in it with an enlarged flame; 13. Of the phenomena attending the diminution of nitrous air by iron filings and brimstone; 14. Of the diminution of nitrous air; 15. Of the nitrous acid extracted from nitrous air; 16. Miscellaneous experiments relating to nitrous air; 17. An account of some experiments made in consequence of an attempt to confine the nitrous acid vapour by means of animal oils; 18. Observations on the nitrous acid vapour itself; 19. Of the saturation of water with nitrous vapour; 20. Of the impregnation of oils, and of spirit of wine, with the nitrous vapour; 21. Of the impregnation of the acids, etc., with the nitrous vapour; 22. Of the actions of nitrous vapour upon some solid substances; 23. Various observations relating to the process for making spirit of nitre; 24. Observations relating to the colour and strength of the nitrous acid; 25. Of the effects of the solution of bismuth and of distillation on the nitrous acid; 26. Experiments relating to inflammable air; 27. Observations relating to vitriolic acid air; 28. Observations relating to fluor acid air; 29. Experiments relating to marine acid air; 30. Experiments on the mixture of different kinds of air; 31. Of the effects of fixed air on vegetation, and the colour of rose leaves; 32. Observations relating to the production, or non-production of air; 33. Miscellaneous experiments; 34. Experiments relating to some of the preceding sections, made since they were printed off; Appendix.