13 



Report on the application of the su?n assigned for Tide Calcu- 

 lations to Mr. Whewell, in a Letter from T. G. Bunt, 

 Esq., Bristol. 



[With two Plates,] 



Bristol, August, 1839. 



Dear Sir, 

 I SEND you eleven new tide-sheets, Nos. 33 to 43, containing dis- 

 cussions of my new tide-gauge observations made between Sep- 

 tember 1837 and June 1839, together with two of the former 

 sheets, Nos. 25 and 29, showing the correction-curves of hmar 

 parallax and declination from the dock observations of 1836 and 

 1837. I have also added several new correction-curves to those 

 of lunar parallax and declination merely, on sheet No. 29, arising 

 out of my investigations of the solar effects on the times of 

 H.W. ; and my numerical calculations, undertaken for the pur- 

 pose of reconciling the discrepancy between the declination- 

 curves, numerically and graphically obtained. My suspicions 

 fell on the latter, as I have already informed you ; but after a 

 long and laborious scrutiny I found that the others were most 

 in fault. All the lunar correction-curves hitherto obtained were, 

 however, defective, for want of applying the solar correction, 

 the introduction of which has considerably altered and, I hope, 

 improved them. 



From the unexplaitied residues of time and of height contained 

 in the sheets for 1834, 5, 6, and 7j (44^ anterior epoch,) I ob- 

 tained the corrections for solar effect, first in a series of 24 



r8"*45 1 

 clination and -< o//.>-q V parallax. The solar correction was 



also found by means of the numerical calculations of the times 

 of H.W. for 1834, 5, 6, 7? and 1838, which was calculated twice. 

 The results may be seen in sheet No. 29. Another arrangement 

 was made from the residues of time on the sheets for 1834, 5, 

 and G, for the declination corrections of 5°, 13°, 20°, and 25*^. 

 The results, which are laid down on sheet No. 29, strongly favour 

 the supposition that the effects of the declinations are as their 

 squares. My latest declination-curves on sheet No. 3 7, for 8°, 19°, 

 and 26°, are still more decisive ; the sum of the twelve ordinates 

 between the lines of 8° and 19° being to those between 19° and 



