134 M. Le Chev. Burg's Improvements of the Lunar Tables. 



and phenomena now described may affect some interesting 

 questions in geology, I shall not presume to inquire ; but I 

 think I may be permitted to remark in conclusion, that we 

 have now specimens of the new red sandstone, containing im- 

 pressions of quadrupeds^ impressions which, to say the least, 

 may be denominated, Footsteps before the Flood. 



Art. XXII. — On the Improvements in the Elements of the 

 Moon's Orbit. By M. Ee Chevalier Burg,* Correspond- 

 ing Member of the Academy of Sciences, F.R.S.E. &c. &c. 

 In a Letter to Dr Brewster. 



i. AM glad to perceive from your letter that you have been in- 

 terested in the communication which I sent you two years ago 

 respecting my investigations into the elements of the lunar or- 

 bit. I have continued these researches without intermission, 

 and I am resolved to occupy myself with them during the rest 

 of my life. My principal object is to establish several epochs 

 in order to decide the question, whether or not the mean mo- 

 tion of the moon is modified by an equation still unknown. I 

 have, however, no intention of neglecting the correction of the 

 other elements, and the more so as I am convinced that most 

 of the coefficients of the equations of longitude may be dedu- 

 ced with certainty to half a second^ and that the epochs deter- 

 mined will be as much more certain as the tables with which 

 the observations are compared are exact. I have indeed already 

 corrected almost the half of the equations of longitude, and as 

 soon as I have done this with the rest, I shall calculate the se- 

 lect observations of Bradley in order to establish the epoch of 

 1755. If I live long enough to be able also to determine the 

 epochs of 1802 and 1825, or 1830, we may consider the above 

 mentioned question resolved. It is true that we can only ar- 

 rive at this by employing much time and labour, but as analy- 

 sis has not yet afforded the solution, and is not likely to do it 



• This distinguished astronomer obtained the prize offered by the Board 

 of Longitude at Paris in 1800 for the best Lunar Tables, and since that 

 time lie has been incessantly occupied in the improvement of that great 

 work. These Tables were published by Dr Vince in the Third Volume of 

 his Asironomv* 



