London: C. Baldwin. 1st Edition. TWO VOLUME FIRST EDITION OF THE FIRST MODERN ATTEMPT TO CONSTRUCT A THEORY OF ATOMIC STRUCTURE. In the first of the two papers, “the English chemist William Prout observed that the atomic weights of the elements known at that time appeared to be whole multiples of the atomic weight of hydrogen, which has been since called the “whole number rule.” This was the first rudimentary theory of the internal structure of an atom” (History of Physics: The Wenner Collection).
In the second paper, published the following year, Prout went further and proposed that the atoms of all other elements were composed of hydrogen atoms. These two assertions, the whole number rule and hydrogen as the universal atomic building block, became known as “Prout’s hypothesis.” Prout's whole number rule was finally proven correct more than a century later in 1919 by British physicist William Aston.
In 1789, Antoine Lavoisier produced the first modern list of chemical elements, containing also the 23 elements then known. Lavoisier died in 1794 and in the years following his death, another 32 were added. “In 1815 Prout, using Avogadro’s method of comparing the relative densities and weights of gases, proposed that all atoms appeared to have weights that were exact multiples of the weight of the lightest atom, hydrogen, and that the different atomic weights of elements are whole-number multiples of the atomic weight of hydrogen (Prout’s hypothesis).
“He took this as proof that all atoms were actually made from hydrogen atoms and the idea was adopted as atomic theory and used for later investigations of atomic weights and the classification of the elements. If all atoms are made from atoms of hydrogen, then it could be possible to transform an atom of one element into an atom of another. If atoms had been assembled from other things, then they could not themselves be the smallest things in creation” (Neilsen, Atomic Weight, A History of Science). Item #773
CONDITION & DETAILS: London: C. Baldwin. 4to. Volume VI: [vii], 479 pages, , 4. 6 plates. Volume VII: [viii], 488 pages, . 10 plates. Both volumes very handsomely rebound in three-quarter calf over marbled paper boards (purposefully rubbed a bit by the conservator for aging). Five raised bands at the spine; elaborate gilt-tooling in the compartments; gilt lettered at the spine. New endpapers. Bright and exceptionally clean throughout. Near fine condition.