"The improvements I would propose in the use of tests are, that the exact quantities of the ingredients in each test should be previously ascertained and marked on the label of the bottle; this might easily be done in most of them in the present state of chemical science. We should then drop in certain quantities of each from a dropping tube graduated into grains till the required effect was produced; then from the quantity of the test required, the quantity of saline matter in the water might be determined without the trouble of collecting the precipitate; or if this was done, the one method might be a check upon the other.” This method of testing, which promises to be of such great value in saving the time of chemists, was then clearly seen by him, although it has taken several workers in the field to bring it into use in the laboratory, chemists, like others, being difficult to move into a new train of thinking and acting. At the same time the mere advice is not enough, it is needful to show how it may be accomplished in various instances; this, Dalton did partially. He gave the right directions as a master, leaving it for a long train of workmen to carry out his ideas. Still we see clearly that he was accustomed to use the graduated dropping tube, and analyze by volume. He gives directions for taking the alkalinity of water by the use of acids, and adds, that "these acids may be considered as sufficient for tests of the quantity of lime in such waters, and nothing more is required than to mark the quantity of acid necessary to neutralize the lime." Here we see that he was accustomed to take the alkalinity of waters for the carbonate of lime. There is certainly a change in the style of these memoirs, there is less care, there are opinions thrown out and unfinished experiments which do not directly lead to benefit, and there is a diminished desire to give the ultimate laws on which phenomena depend. The mind had evidently felt that something had been achieved, which left it leisure and gave it also a right to be heard, even when it uttered only its suspicions. In these memoirs we find prominently brought forward that intense faith in his own previous results, constantly quoting what was obtained in his own mind in preference to the results obtained by the whole world besides. This gradually led to a certain amount of egotism, and a conservative belief that all work in that direction was completely finished, so that he does not seem to look forward sufficiently to any improvement or modification. Instead of reviewing his later writings, I shall add here a list more complete than has been yet given, although all the papers were not viewed by him as important, and some were merely given in all probability to supply an occasional want of material at the meetings of the Literary and Philosophical Society; by a perusal of the titles some idea will be given of his great fertility and diligence. These titles are taken from the books of the Society. On reading them over, one is compelled to wonder at the newness and youth of much of our modern science, and to doubt, on that account, the stability of not a few of its maxims; for we find that although it is intended to represent the thoughts of nature, it is of itself not older than "a man that shall die." After Dalton read his first paper, Mr. Robert Owen read one on March 6th, 1795, entitled "Thoughts on the connection between universal happiness and practical mechanics;" and in 1797, "On the origin of opinion with a view to the improvement of the social virtues." Mr. Owen is still alive. LIST OF DALTON'S PAPERS. Read before the Members of the Manchester Literary and Philosophical Society. 1. October 31st, 1794. Extraordinary Facts relating to the Vision of Colors, with Observations. 2. November 27th, 1795. On the Color of the Sky, and the relation between Solar Light and that derived from Com bustion; with Observations on Mr. Delaval's Theory of Colors. 3. April 7th, 1798. Essay on the Mind, its Ideas, and Affections; with an Application of Principles to explain the Economy of Language. 4. March 1st, 1799. A paper, containing Experiments and Observations, to determine whether the quantity of Rain and Dew is equal to the quantity of Water carried off by the rivers and raised by evaporation; with an Inquiry into the Origin of Springs. 5. April 12th, 1799. Experiments and Observations on the Power which Fluids possess of conducting Heat; with Reference to Count Rumford's seventh essay. 6. June 7th, 1799. On the Color of the Sky, and the relation betwixt Solar Light and that derived from Combustion; with Observations on Mr. Delaval's Theory. 7. April 18th, 1800. Experimental essays, to determine the Expansion of Gases by Heat, and the maximum of Steam or Aqueous Vapour, which any Gas of a given temperature can admit of; with observations on the common and improved Steam Engines. 8. June 27th, 1800. On the Heat and Cold produced by the Mechanical Condensation and Rarefaction of Air. 9. October 17th, 1800. Philological Inquiry into the Use and Signification of the Auxiliary Verbs and Participles of the English Language. 10. December 12th, 1800. Review of Dr. Herschel's Experiments on the radiant Heat, and the Reflectibility and Refrangibility of Light. 11. July 31st, 1801. Read Part 1st of Mr. Dalton's paper on the Constitution of Mixed Gases, &c. 12. October 2nd, 1801. Read, Part 2nd of Mr. Dalton's paper on the Force of Steam, &c. 13. October 16th, 1801. Read Part 3rd of Mr. Dalton's paper on Evaporation, &c. 14. January 22nd, 1802. On the General Causes, Force, and Velocity of Winds; with remarks on the Seasons most liable to high winds. 15. October 29th, 1802. On the Proportion of the several Gases or Elastic Fluids, constituting the Atmosphere; with an Inquiry into the Circumstances which distinguish the Chymical and Mechanical Absorption of Gases by Liquids. 16. January 14th, 1803. On the Spontaneous Intercourse of different Elastic Fluids, in confined circumstances. 17. October 7th, 1803. On the Absorption of Gases by Water. 18. November 4th, 1803. Elastic Fluids, Liquids, and On the Law of Expansion of Vapours. 19. February 24th, 1804. A Review and Illustration of some Principles in Mr. Dalton's course of Lectures on Natural Philosophy, at the Royal Institution, in January, 1804. 20. August 3rd, 1804. Philosophy. 21. October 5th, 1804. 22. November 30th, 1804. On the Elements of Chemical On Heat. Review of Dr. Hope's paper "On the Contraction of Water by Heat." 23. September 2nd, 1805. Remarks on Mr. Gough's two Essays on Mixed Gases, and on Mr. Schmidt's, "On Moist Air." 24. March 7th, 1806. On Respiration and Animal Heat. On the Constitution and Pro 25. February 6th, 1807. perties of Sulphuric Acid. 26. October 2nd, 1807. 27. October 16th, 1807. by Heat. 28. January 22nd, 1808. 29. March 18th, 1808. Bodies. On Heat. On the Expansion of Bodies On the Specific Heat of Bodies. On the Specific Heat of Gaseous 30. December 2nd, 1808. On the Measure of Mechanical Force. 31. December 16th, 1808. On Respiration. 32. March 10th, 1809. On Evaporation. 33. April 7th, 1809. On the Compounds of Sulphur. 34. November 3rd, 1809. On Muriatic Acid. 35. December 1st, 1809. On Sulphuric Acid. 36. March 9th, 1810. On Fog. 37. November 16th, 1810. Appendix to his Remarks on Respiration and Animal Heat. 38. December 28th, 1810. On Hygrometry. 39. April 3rd, 1812. 40. April 17th, 1812. 41. October 2nd, 1812. 42. January 8th, 1813. and the Phosphates. On Meteorology. 43. March 5th, 1813. the different Compounds of 44. October 1st, 1813. 45. October 15th, 1813. the Combinations of Gold. Meteorology continued. On the Oxymuriate of Lime. Experiments and Observations on 46. November 12th, 1813. The Combinations of Platina. Mixtures. Experiments on certain frigorific 49. March 18th, 1814. Remarks tending to facilitate the Analysis of Spring and Mineral Waters. 50. October 7th, 1814. On Metallic Oxides. 51. December 2nd, 1814. tinued.) 52. January 27th, 1815. modern Chemical Phrases. 53. November 17th, 1815. On Metallic Oxides. (Con Critical remarks on some Remarks on Saussure's Essay on the Absorption of Gases by Liquids. 54. October 4th, 1816. On the chemical compounds of Azote and Oxygen. |