60 ^^p^y io Dr. Kelly's Letter on his supposed 



been stated to have been used, or whether it did not. If" the 

 declination did not agree with the obHquity, it would be a 

 clear proof that some mistake existed in either the assumed 

 obliquitv, or the declination computed from it. But in the 

 case in question the declination at the two solstices agrees 

 with the obliquitv as it ought to do. 



It seems therefore extraordinary, that Dr. Kelly, who 

 " has been for manv years in the constant practice of 

 teaching mathematical students to compute the columns 

 of the Nautical Almanac," should not have been aware of 

 this circumstance, and thereby evaded the trouble of mak- 

 ing suck riumerovs calculations. It is hard to say indeed, 

 whether the Doctor's joy arising upon the merit that he 

 conceived would be attached to his discovery induced him 

 to actiiallv make these calculations, or the desire of com- 

 pleting the sentence in order to recommend his book upon 

 Spherics, was the motive for such a declaration ; but, per- 

 haps, this inference may appear a little deficient in candour 

 towards the Doctor. Should it be so thought, I can only 

 reply, it is in the Doctor's own way of considering things, 

 as I believe I shall by and by make appear. 



Whatever might be the reason which induced the Doctor 

 to make these calculations in preference to the simple com- 

 parison of the stated obliquity of the ecliptic with the sun's 

 declination at the two solstices, is perhaps immaterial : it 

 mav be of more consequence, in the present view of the 

 subiect, to notice the merits of his book upon Spherics, to 

 which our attention has been directed in the latter part of 

 this sentence. We are told, that he believes his " work on 

 Spherics and Nautical Astronomy is the only publication 

 where such calculations are particularly exemplified." 



The reader, therefore, would be iuiluced to conclude, from 

 such statement, that this book must be a valuable acquisition 

 to the computers of the Nautical Almanac, that it contains 

 lu/merous c\a.m\Aes and illustrations of the method of calcu- 

 lating the various particulars contained in the columns of the 

 Nautical Almanac. Nay, he would fancy he should meet in 

 its perusal, with the methods of computing, not only what 

 relates to the sun, but certainly to the moon, from its being 

 a work of navuical practice,, and perhaps of the planets also. 

 But how much would such a reader be diasppoinled, if, when 

 he came to read this valuable composition, he should find 

 that not a single example existed in the whole book of such 

 compulation? ! and yet, after all the boasted panegyric on 

 it, not a >inglc example strictly speaking does exist of such 

 computations. 



I shall 



