Page:Dictionary of National Biography volume 13.djvu/439

 Petit's researches on heat he was more respectful. Indeed their law of specific heats, enunciated in 1819, had been in part anticipated by his statement in 1808, that ‘the quantity of heat belonging to the ultimate particles of all elastic fluids must be the same under the same pressure and temperature’ (New System, i. 70).

In 1832 and 1834 honorary degrees of D.C.L. and LL.D. were conferred upon Dalton by the universities of Oxford and Edinburgh respectively. He constantly attended the meetings of the British Association, acting as vice-president of the chemical section at Dublin in 1835, and at Bristol in 1836. In 1834 his friends employed Chantrey to execute a marble statue of him; and while the necessary sittings were in progress in London, Babbage persuaded him to allow himself to be presented at court. As a quaker he could not wear a sword; so he went attired in his scarlet doctor's robes, with the less scruple on the score of their brilliancy that to his own eyes they were undistinguishable in hue from grass or mud.

Meanwhile Babbage, Chalmers, and other well-wishers were anxious to see him relieved from the drudgery of teaching; and the success of their efforts to procure him a pension was formally announced by Professor Sedgwick at the Cambridge meeting of the British Association in 1833. From 150l. a year it was increased to 300l. in 1836, while the devolution upon him, by the death of his brother in 1834, of the paternal estate augmented by purchase, raised him to comparative wealth. He did not therefore relax his industry. He sent to the Royal Society in 1839 an essay ‘On the Phosphates and Arseniates,’ which proved too feeble and obscure to be inserted in the ‘Philosophical Transactions.’ Deeply mortified, he had it printed separately, adding to the note intimating its rejection the remark, ‘Cavendish, Davy, Wollaston are no more.’ Two of four short papers collectively published in 1842, ‘On a new and easy Method of Analysing Sugar,’ and ‘On the Quantities of Acids, Bases, and Water in the different Varieties of Salts,’ announced the discovery, prosecuted by Playfair and Joule, that certain salts rendered anhydrous by heat add nothing to the volume of the water they are dissolved in, the solid matter ‘entering into the pores’ of the liquid.

The Johns family left Manchester in 1830, and Dalton thenceforth lived alone. His friend, Mr. Peter Clare, however, attended him devotedly during his last years of infirmity. On 18 April 1837 he had a shock of paralysis, which recurred in the following year, and left him with broken powers. Impaired utterance hindered him from assuming the office, otherwise designated for him, of president of the British Association at Manchester in 1842. He had another slight fit 20 May 1844, and made a last feeble record of the state of the barometer on 26 July. On the following morning he fell from his bed in attempting to rise, and was found lifeless on the floor. He was in his seventy-eighth year. His remains, placed in the town hall, and there visited, during four days, by above forty thousand persons, were escorted 12 Aug. by a procession of nearly one hundred carriages to Ardwick cemetery. His memory was fittingly honoured by the foundation of two chemical and two mathematical scholarships in connection with Owens College.

Several portraits of Dalton exist. One painted by Allen in 1814 adorns the rooms of the Manchester Philosophical Society. An engraving from it is prefixed to Dr. Angus Smith's ‘Memoir.’ Another by Phillips showing the advance of age belonged to Mr. Duckworth of Beechwood. Chantrey's fine statue stands in the entrance hall of the Manchester Royal Institution. A bronze copy of it was placed after his death in front of the Royal Infirmary. Dalton was always unexceptionably dressed in quaker costume—knee-breeches, dark-grey stockings, and buckled shoes. His broad-brim beaver was of the finest quality, his white neckcloth spotless, his cane gold or silver headed. The members of the British Association were forcibly struck at Cambridge in 1833 with his likeness to Roubiliac's statue of Newton. In society he was unattractive and uncouth, sometimes presenting to strangers the appearance of moroseness. Importunate questionings about his discoveries he was wont to cut short with the reply: ‘I have written a book on that subject, and if thou wishest to inform thyself about the matter, thou canst buy my book for 3s. 6d.’ (, John Dalton, p. 255). Yet he was fundamentally gentle and humane. Those who saw most of him loved him best, and his friendship, once bestowed, was inalienable. He had a high respect for female intelligence, paid to women an almost chivalrous regard, and honoured some with a warm attachment. He was alive to the beauties of nature, enjoyed simple music, and in his youth wrote indifferent poetry. His kindliness and love of truth are exemplified in the following anecdote: ‘A student who had missed one lecture of a course applied to him for a certificate of full attendance. Dalton at first declined to give it; but after thinking a little replied, “If thou wilt come to-morrow, I will go over the lecture