On Oxalic Acid. Read January 14th, 1808. (Thomson) (+) On Super-acid and Sub-acid Salts. Read January 28, 1808. (Wollaston). 2 Papers.

(London, W. Bulmer and Co., 1808). 4to. No wrappers as extracted from "Philosophical Transactions" 1808 - Part I. Pp. 63-95 (Thomson) and pp. 96-102 (Wollaston:). Clean and fine. First appearance of these two historical papers in chemistry in which Thomson and Wollaston, independently, presents experimental proofs of John Dalton's "Law of Multiple Proportions", and thereby laying the foundations of the Atomic Theory. - These demonstrations went far to influence chemists favorably toward Dalton's atomic theory. "In January 1808 Thomson was the first to submit an experimental illustration of the law of multiple proportions, doing so at least four months before the publication of Dalton's "New System of Chemistry Philosophy" (1808). This paper, "On Oxalic Acid" also established a usefull method of determining empirical formulas."(DSB XIII, p. 373)."This paper is also importent as he here introduces quantified chemical symbolism for compounds, a compound with, for instance, two parts oxygen (w) and one part carbon (c) being denoted by 2w + c." (Parkinson in "Breakthroughs", 1808 C)."In 1808 he (Wollaston) described his experiments on carbonates, sulfates, and oxalates, which proved that the composition of these substances was regulated by the law of multiple proportions. These additional instances of the law were easely verifiable and were often mentioned as standard examples. Wollaston accepted that his findings were merely particular instances of Dalton's assertion that the atoms of elements united one to one, or by simple multiple relation."(DSB XIV, p.488).…