xiv Mr. Pickering’s Eulogy on 
reached America, Dr. Bowditch had published, in one of our 
journals, a statement of the elements of it; and he came to the 
conclusion (which was afterwards found to be correct), that the 
comet in question was one which was before unknown to astrono- 
mers.* I allude to this circumstance, not by way of proving that 
he had displayed what he would himself have considered as 
evidence of mathematical powers, but as one, among numerous 
instances, to show, that results then obtained by him, as well as by 
eminent foreign astronomers, might be safely relied upon. 
In the same volume of the Memoirs is his valuable paper con- 
taining “Observations on the remarkable Total Eclipse of the Sun, 
which happened on the 16th of June, 1806.” This is the more in- 
teresting, as it contains, in the modest form of a JVole, the first public 
mention made by him of an error in La Place’s Mécanique Céleste, 
in the estimate of the oblateness of the earth. Dr. Bowditch, in 
determining the latitude of his place of observation, assumed the 
difference between the equatorial and polar diameters of the earth 
to be s3ath; which, he adds, is conformable to the Tables of La 
Lande; but La Place, from the observed length of pendulums, 
had calculated the ellipticity at 335th; in which, Dr. Bowditch ob- 
serves, a small mistake was made in one of the equations, which, 
if corrected, would make the result, that La Place should have given 
on his own principles, 3tsth ; which does not differ much from 335th, 
the result deduced by La Place himself from the lunar theory.t 
The next memoir by Dr. Bowditch was one of great practical 
value ; an “ Application of Napier’s Rules for solving the Cases of 
Right-angled Spheric Trigonometry to several Cases of Oblique- 
angled Spheric Trigonometry ”; in which, by a small alteration in 
the expression of those rules, they are made to include the solu- 
* Mem. Amer. Acad. Vol. III. p. 1. t Ibid. p. 18. 
