18 AN ACCOUNT OF THE EARLY MATHEMATICAL AND 



the top of the vessel. It is required to find how much higher 

 the water will rise in the tube when the barometer falls to 

 28*5 ; the temperature being the same." Answer, 13*5 inches 

 nearly.* 



His contributions to the Ladies Diary for 1792 are not so 

 extensive as in former years. Ho furnished solutions to all 

 the philosophical queries — three of which obtained insertion ; 

 and also to seven questions in the mathematical department of 

 the Diary and its Supplement. Most of these are of an easy 

 character, and could have added but little to his already well- 

 established reputation. The editor, however, remarks in the 

 Supplement, " that the ingenious answer to the prize question 

 in the Diary by Mr. John Dalton was inserted in the copy 

 but was obliged to be omitted at the press for want of room." 

 In answer to the first query he asserts that " the pleasure 

 arising from conferring an obligation, especially if it be 

 eflfected without much inconvenience, is pure, and must be a 

 grateful sensation to a generous mind ; — but that arising from 

 receiving an obligation is often mixed with the unpleasing 

 reflection of inability to remunerate the benefactor;'* — hence 

 he concludes that the pleasure arising from the former must 

 be greater than that arising from the latter. The second 

 query conveys his sentiments relative to second marriages. 

 He is of opinion that persons "of sensibility and virtue" 

 are capable of feeling " an equal passion for another object," 

 and " consequently the query may be answered in the 

 affirmative." In his third answer he remarks that " probably 

 spirits dissolve sugar solely by reason of the water they 

 contain, and this being only a part of their composition, 

 renders the solution more slow than when the menstruum 

 is pure water." 



* Mr. Dalton s object in proposing tliis question appears to have been the 

 graduation of a water barometer. A well-constructed instrument of this 

 description would obviously exhibit a large rise in the tube for a sinall variation 

 of density in the atmosphere, but capillary attraction and the length of the 

 apparatus required would materially interfere with its practical utility. 



