Dalton's theory incurred much opposition before it was finally accepted by scientific men, and among the unbelievers in it may be mentioned Sir Humphry Davy. The baronet, however, in the year 1826, clearly acknowledged and accurately defined Dalton's discoveries in his anniversary discourse, when he made known that the first award of the Royal Society's Prize, founded by George IV. in the year before, would be given to Mr. John Dalton, "for the development of the chemical theory of Definite Proportions, usually called the Atomic Theory, and for his various other labours and discoveries in physical and chemical science." During his later life Dalton continued to gain his living as professional chemist, lecturer, and teacher of Chemistry and Mathematics, and contributed to the advancement of science many valuable papers chiefly relating to Chemistry; he was also accustomed in his analytical researches to use the graduated dropping tube, and may be considered as the originator of analysis by volume. Mr. Dalton was present at the first meeting of the British Association held in York in 1831, and continued to feel a lively interest in its prosperity, and to attend the annual meetings as long as his health permitted him. On the occasion of the second meeting at Oxford in 1832, the honorary degree of D.C.L. was conferred upon him, in conjunction with Faraday, Brown the botanist, and Sir David Brewster. In the summer of the following year, at the meeting of the same society in Cambridge, it was announced by Professor Sedgewick, that the King had conferred on Dalton a pension of 150_l._ per annum, which was increased in 1836 to 300_l._; and as his brother Jonathan died about the same time and left him heir to the paternal estate, he became comparatively wealthy. He, however, still continued working according to his strength, and so late as 1840 published four Essays, entitled, 'On the Phosphates and Arseniates;' 'Microcosmic Salt;' 'Acids, Bases, and Water;' and 'A New and Easy Method of Analysing Sugar.' In 1837-8 Dalton was attacked by paralysis, which greatly enfeebled him; he, however lived till the year 1844, when a third attack occurred, from which he never recovered, but died shortly afterwards in his seventy-eighth year.