Mr. Daniell on the Barometer, 93 



whilst in Capt. Rater's memoir in the Philosophical Transactions, it 

 is stated to he 83 feet only ; it is necessary to explain that Capt. 

 Rater's estimation of the height was founded, in part, on the un- 

 derstanding (on the autliority of the Royal Society) that the elevation 

 of their barometer at Somerset-House is 81 feet above low-water 

 mark ; hut as the latter elevation has been since corrected by Mr. 

 Bevan, who has determined it, by levelling, to be 90.5 feet above 

 the mean level, the height of the pendulums must now be con- 

 sidered as 92.5 feet, and is so esteemed by Captain Rater*." 



The same national work is also much affected by the want of 

 such standard instruments as it is the appropriate province of the 

 Royal Society to provide and preserve. Is it to be tolerated that 

 results of such national importance should be made to depend for 

 their verification upon a comparison with a thermometer, the pro- 

 perty of a private individual ? The uncertainty in the experi- 

 ments arising from such a cause may, according to Captain 

 Sabine, amount to " not less than T %th of a vibration per diem ; 

 being greater, as he had reason to believe, than the sum of the 

 uncertainties due to all other causes whatever t." 



Surely these considerations, urged from so many quarters, must 

 at length excite the dormant energies of those to whom the honour 

 of the Royal Society i3 committed. If it be more consistent with 

 the dignity of that venerable body to give up the working depart- 

 ments of science, and to sit as judges only of the exertions of 

 others, let them announce such intention openly, and there will 

 then be many come forward in the field from which they retire. 

 In most branches of science this is the course which has been 

 already adopted ; and yet they have, perhaps, enough to do as im- 

 partial dispensers of those honours for which there are so many 

 competitors. But if they are still determined to persevere in causing 

 observations to be made " by their order," in the only branch of 

 natural science which now remains to them, let them at least pro- 

 vide that they be made with all the care and precision which the 

 actual state of that science demands ; for upon this the honour 

 of the Society is at stake. 



* Experiments for determining the figure of the Earth. By Edward Sabine, 

 &c. p. 343. t Idem. p. 182. 



