Dr Heineken on the Mean Temperature of Funchal. 41 



servation ; and the observer, (Mr J. Murdoch,) was, I sus- 

 pect, a mere noter of weather-glasses, and perfectly innocent 

 of all scientific attainments. BowdicK's were continued but 

 for a short period, and in a desultory manner. I cannot un- 

 derstand in what way the blanks ( ,, ) in his monthly means 

 are to be filled up ; and he does not himself state in direct terms 

 what he considers his own annual mean. It is therefore only 

 left to me, {after excluding what would otherwise appear to 

 be my own evidence against myself (the 1824 and 1825 means) 

 on the ground that I hnew them to be incorrect, and never pub- 

 lished them as true means,) to suggest, that, as the mode ge- 

 nerally in use for obtaining maxima observations is at best but 

 an approximation to the truth, and as mine, although / may 

 see reason sufficient for giving it the preference, at least wants 

 confirmation, we should adopt a mean, derived from the three 

 unimpeached previous deductions, and what / consider as those 

 only of mine (three also) which approximate the truth ; instead 

 of that which the Editor has suggested in the last Journal. 

 It will then stand thus : — 



Humboldt, 68.5 



Brewster, 68.7 



Heberden, 67.3 



Mine for 1826, 64.3 



1827, Q5.Q 



1828, Q5.Q 

 giving 66.7 for the mean. ^ 

 Or, if it did notlook self-opiniatedand presumptuous, I mustown 

 that I would go a little farther, and say 66.3; the result of Dr 

 Heberden's,* (67.3), and my 2 years mean (65.2); and I would 

 do so, because they were both derived Jrom personal and co7i^i- 

 ww^6/ observations, which won^ of the others I believe, (Gourlay's 

 and Bowdich's being placed hors de combat for the reasons 

 given), were, and because I cannot attribute the cause of mine 

 being lower than all others to the situation having been artifi- 

 cially cooled, knowing that whatever slight artificial draught it 

 might have acquired was at least compensated by the winds, 

 from which it was occasionally sheltered, and the artificial heat 

 which it necessarily acquired, during the four days in the win- 



• Dr Heberden was a resident in Funchal during several years. 



