ELECTIVE AFFINITY

( Wahlverwandtschaft , Germ.) denotes the order of preference, so to speak, in which the several chemical substances choose to combine; or really, the gradation of attractive force infused by Almighty Wisdom among the different objects of nature, which determines perfect uniformity and identity in their compounds amidst indefinite variety of combination. The discu ion of this interesting subject belongs to pure chemistry. See Decomposition . ELEMENTS (Eng. and Fr.; Grundstoffe , Germ.) The ancients considered fire, air, water, and earth, as simple substances, e ential to the constitution of all terrestrial beings. This hypothesis, evidently incompatible with modern chemical discovery, may be supposed to correspond, however, to the four states in which matter seems to exist; namely, 1. the unconfinable powers or fluids,—caloric, light, electricity; 2. ponderable gases, or elastic fluids; 3. liquids; 4. solids. The three elements of the alchemists, salt, earth, mercury, were, in their sense of the word, mere phantasms. In modern science, the term Element signifies merely a substance which has not yet been resolved by analysis into any simpler form of matter; and it is therefore synonymous with unde compounded. This cla comprehends 54 different bodies, of which no le than 41 are metallic. Five may be styled Archæal , from the intensity and universality of their affinities for the other bodies, which they penetrate, corrode, and apparently consume, with the phenomena of light and heat. These 5 are chlorine , oxygen , iodine , bromine , fluorine . Eight elements are eminently inflammable when acted upon by any of the preceding five, and are thereby converted into incombustible compounds. The simple non-metallic inflammables are hydrogen , azote , sulphur , phosphorus , selenium , carbon , boron , silicon . The following table exhibits all the unde compounded bodies in alphabetical order, with their prime equivalent numbers, atomic weights, or reciprocal combining and saturating proportions, as given by Berzelius, in reference to oxygen, reckoned 100,000. :— Table of unde compounded Bodies, or modern Chemical Elements. A signifies Archæal; I, Inflammable; M, Metal. | Aluminium | M. | 171,167 | | Antimony | — | 806,542 | | Arsenic | — | 470,042 | | Azote | I. | 88,518 | | Barium | M. | 856,880 | | Bismuth | — | 886,000 | | Boron | I. | 135,983 | | Bromine | A. | 489,150 | | Cadmium | M. | 696,970 | | Calcium | — | 256,019 | | Carbon | I. | 76,437 | | Cerium | M. | 574,718 | | Chlorine | A. | 221,325 | | Chromium | M. | 351,819 | | Cobalt | — | 369,991 | | Copper | — | 395,695 | | Fluorine | I. | 116,900 | | Gold | M. | 1243,013 | | Hydrogen | I. | 62,398 | | Iodine | A. | 789,145 | | Iridium | M. | 1233,260 | | Iron | — | 339,213 | | Lead | — | 1294,489 | | Lithium | — | 81,320 | | Magnesium | — | 158,353 | | Manganesium | — | 345,900 | | Mercury | M. | 1265,822 | | Molybdenum | — | 598,525 | | Nickel | — | 369,675 | | Osmium | — | 1244,210 | | Oxygen | A. | 100,000 | | Palladium | M. | 665,840 | | Phosphorus | I. | 196,155 | | Platinum | M. | 1233,260 | | Rhodium | — | 651,400 | | Selenium | I. | 494,582 | | Silicon | — | 277,478 | | Silver | M. | 675,804 | | Strontium | — | 547,285 | | Sulphur | I. | 201,165 | | Tantalum | M. | 1153,715 | | Tellurium | — | 801,760 | | Thorinum | — | 744,900 | | Tin | — | 735,294 | | Titanium | — | 303,686 | | Tungsten | — | 1183,000 | | Uranium | — | 2711,360 | | Vanadium | — | 855,840 | | Yttrium | — | 401,840 | | Zinc | — | 403,226 | | Zirconium | — | 420,238 |