Ternary
Quaternary
Quinquenary & Sextenary
Septenary
The illustration on the preceding page contains the arbitrary marks or signs chosen to represent the several chemical elements or ultimate particles.
Fig. 1. Hydro. its rel. weight 1 2. Azote 5 3. Carbone or charcoal 5 4. Oxygen 7 5. Phosphorus 9 6. Sulphur 13 7. Magnesia 20 8. Lime 23 9. Soda 28 10. Potash 42 11. Strontites 46 12. Barytes 68 13. Iron 38 14. Zinc 56 15. Copper 56 16. Lead 95 17. Silver 100 18. Platina 100 19. Gold 140 20. Mercury 167 21. An atom of water or steam, composed of 1 of oxygen and 1 of hydrogen, retained in physical contact by a strong affinity, and supposed to be surrounded by a common atmosphere of heat; its relative weight = 8 22. An atom of ammonia, composed of 1 of azote and 1 of hydrogen 6 23. An atom of nitrous gas, composed of 1 of azote and 1 of oxygen 12 24. An atom of olefiant gas, composed of 1 of carbone and 1 of hydrogen 6 25. An atom of carbonic oxide composed of 1 of carbone and 1 of oxygen 12 26. An atom of nitrous oxide, 2 azote + 1 oxygen 17 27. An atom of nitric acid, 1 azote + 2 oxygen 19 28. An atom of carbonic acid, 1 carbone + 2 oxygen 19 29. An atom of carburetted hydrogen, 1 carbone + 2 hydrogen 7 30. An atom of oxynitric acid, 1 azote + 3 oxygen 26 31. An atom of sulphuric acid, 1 sulphur + 3 oxygen 34 32. An atom of sulphuretted hydrogen, 1 sulphur + 3 hydrogen 16 33. An atom of alcohol, 3 carbone + 1 hydrogen 16 34. An atom of nitrous acid, 1 nitric acid + 1 nitrous gas 31 35. An atom of acetous acid, 2 carbone + 2 water 26 36. An atom of nitrate of ammonia, 1 nitric acid + 1 ammonia + 1 water 33 37. An atom of sugar, 1 alcohol + 1 carbonic acid 35
| Fig. | |
| 1. Hydro. its rel. weight | 1 |
| 2. Azote | 5 |
| 3. Carbone or charcoal | 5 |
| 4. Oxygen | 7 |
| 5. Phosphorus | 9 |
| 6. Sulphur | 13 |
| 7. Magnesia | 20 |
| 8. Lime | 23 |
| 9. Soda | 28 |
| 10. Potash | 42 |
| 11. Strontites | 46 |
| 12. Barytes | 68 |
| 13. Iron | 38 |
| 14. Zinc | 56 |
| 15. Copper | 56 |
| 16. Lead | 95 |
| 17. Silver | 100 |
| 18. Platina | 100 |
| 19. Gold | 140 |
| 20. Mercury | 167 |
| 21. An atom of water or steam, composed of 1 of oxygen and 1 of hydrogen, retained in physical contact by a strong affinity, and supposed to be surrounded by a common atmosphere of heat; its relative weight = | 8 |
| 22. An atom of ammonia, composed of 1 of azote and 1 of hydrogen | 6 |
| 23. An atom of nitrous gas, composed of 1 of azote and 1 of oxygen | 12 |
| 24. An atom of olefiant gas, composed of 1 of carbone and 1 of hydrogen | 6 |
| 25. An atom of carbonic oxide composed of 1 of carbone and 1 of oxygen | 12 |
| 26. An atom of nitrous oxide, 2 azote + 1 oxygen | 17 |
| 27. An atom of nitric acid, 1 azote + 2 oxygen | 19 |
| 28. An atom of carbonic acid, 1 carbone + 2 oxygen | 19 |
| 29. An atom of carburetted hydrogen, 1 carbone + 2 hydrogen | 7 |
| 30. An atom of oxynitric acid, 1 azote + 3 oxygen | 26 |
| 31. An atom of sulphuric acid, 1 sulphur + 3 oxygen | 34 |
| 32. An atom of sulphuretted hydrogen, 1 sulphur + 3 hydrogen | 16 |
| 33. An atom of alcohol, 3 carbone + 1 hydrogen | 16 |
| 34. An atom of nitrous acid, 1 nitric acid + 1 nitrous gas | 31 |
| 35. An atom of acetous acid, 2 carbone + 2 water | 26 |
| 36. An atom of nitrate of ammonia, 1 nitric acid + 1 ammonia + 1 water | 33 |
| 37. An atom of sugar, 1 alcohol + 1 carbonic acid | 35 |
Dalton’s estimations of the relative weights of the atoms, or, to use Davy’s phrase, the values of their combining proportions, were, as might be expected, very rough approximations to the truth. This arose partly from inadequate experimental data, and partly from uncertainty as to the relative number of the constituent atoms which made up a compound. Neither Dalton nor his immediate successors had any rational or consistent method of determining the latter point. The view taken of the composition of the compound decided what particular multiples or sub-multiples of the values of the atomic weights of its constituents were to be adopted. As Dalton, in many cases, had no real criterion to guide him, he made the simplest possible assumptions; but these might or might not be valid; and subsequent experience showed that in some cases they were erroneous.
It was, however, generally recognised that these atomic weights, combining proportions, or equivalents, as they were for a time indifferently termed, were chemical constants of the highest importance, both to the scientific chemist, who, apart from their theoretic interest, had need of them in the course of quantitative analysis, and to the manufacturing chemist, who required them for the intelligent exercise of his operations; and accordingly a number of chemists, very shortly after the promulgation of Dalton’s theory, attempted to determine their values with all possible precision. Chief among these was the Swedish chemist Berzelius, to whom science was indebted for a series of estimations of atomic weights, which were long regarded as models of quantitative accuracy, and stamped their author as the greatest master of determinative chemistry of his age.
Jöns Jakob Berzelius, the son of a schoolmaster, was born near Linköping, in East Gothland, Sweden, in 1779. Entering Upsala with a view to the profession of medicine, he was attracted, under the influence of Afzelius—or, rather, in spite of it—to the study of chemistry, and, later, of voltaic electricity, then in its infancy. While holding a number of minor appointments as a teacher of medicine, pharmacy, physics, and chemistry, he was elected, in 1808, a member of the Swedish Academy of Sciences, of which he became President in 1810. In 1818 he was made permanent Secretary of the Academy, and, by means of a yearly subsidy, was enabled to devote himself wholly to experimental science. He was ennobled in 1818, and on the occasion of his marriage, in 1835, was created a baron of the Scandinavian kingdom. He died in 1848.
Berzelius occupies a pre-eminent position in the history of chemistry, and during a considerable portion of his lifetime exercised an almost unassailable authority as a chemical philosopher. He is distinguished as an experimenter, as a discoverer, as a critic and interpreter, and as a lawgiver. His contributions to chemical knowledge range over every department of the science. He shares with Davy the honour of having established the fundamental laws of electro-chemistry. His experimental work on the atomic weights of the elements—the great work of his life—was of supreme importance at this particular period of the development of chemistry: it served not only to give precision to, and enhance the significance and value of, Dalton’s generalisation, but it furnished chemists, for the first time, with a set of constants, ascertained with the highest exactitude of which operative chemistry was then capable, thereby contributing to the expansion of quantitative analysis, and to a more exact knowledge of the composition of substances. Berzelius, indeed, was an analyst of the first rank—conscientious, patient, and painstaking; an ingenious and skilful manipulator; inventive and resourceful. What determinative chemistry owes to his labours, and not less to his example, is obvious from even the most superficial examination of its literature during the first third of the last century.