17 
Mathematical Collections of' Pappus. 
I 
have them “ en admettant l'interpretation de Commandin us, a 
laquelle Vendelinus n'a pas cru devoir deferer.” M. Lalande 
does not in this place, with his usual precision, point out the 
work of Wendelinus, in which this opinion is to be found, and 
I have looked twice through the “ Loocias sen de ohliquitate 
solis , Antwerpise, 1626,’" without finding it. The passage from 
Pappus is discussed in pages S3, 24. of that work ; but its in- 
congruity with Ptolemy is there accounted for by a mistake in 
the latitude of Alexandria, where the observation is supposed 
to have been made, and by a neglect of allowing 7" for the 
effect of parallax, when the sun was 7° 30' from the zenith. It 
is not, however, worth while to spend time in tracing further, 
since the doubt derives its principal interest from the authority 
which is given to it by Lalande. It is well known that Cornman- 
dine\s book, to say the least, is most carelessly printed, so that if 
no error had been introduced either by the transcriber of the 
Greek text or by the translator, we can feel no certainty of the 
accuracy of the printer. The numbers, indeed, which occur in 
the commentary, agree so well with those in the text of Comman- 
dine, that, in the present instance, there can hardly be any press 
error in the expression of the fundamental ratios ; but still 
there was evidently some general notion of possible mistake in 
the mind of Lalande, who certainly does not mention the sus- 
picions of his author, as if he wholly rejected them. 
Again, M. Delambre ( Astronomic Theorique et Pratique , 
vol. iii. pages 181-2.), after stating the case at some length, and 
after distinctly laying down that Pappus bad no intention of giving 
any precise determination of the obliquity, still seems to feel 
with others the wish to accommodate, if possible, the passage 
in question to what must have been the truth. Pie closes the 
seventh article of Chap, xxxii., by saying, tc Lalande rejette 
sur le traducteur Commandin ferreur de Pappus ; mais, a 
moms de supposer une faute de copie ou d'impression, je ne 
vois pas ce qifon peut objecter a l'interpretation et au commen- 
taire de Commandin qui nest qu'un calcul. Mais lisez 526 
au lieu de 529, et vous aurez * a — 23° 52', ce qui supposera 
a is the symbol used by M. Delambre for the obliquity. 
VOL. V. XO. 9. JULY 1821. 
B 
