2; 0


3, 6;58

4, 0;19

In order to understand the peculiar organization of Bianchini's tables, it is essential to realize that the entries in Tables 12 and 13 for the double elongation, the lunar longitude, and the argument of lunar latitude, do not correspond to the exact number of years indicated in the first column, but to the closest previous time when the lunar anomaly was 0°.

For instance, in the case of the entry for 1 year, 6d 18;59h means that in a year of 365 days there is an integer number of anomalistic months plus 6d 18;59h and, indeed, 6d 18;59h = 365d - (13 ■ 27d 13;18,36h). Thus, the entry for 1 year of 93;41° for the double elongation has to be understood as the increment in double elongation between the beginning of the year and this precise moment (6d 18;59h before the completion of the year) at the rate of 2 ■ 12;11,27°/d, the standard parameter used in Alfonsine astronomy for the double elongation.

Table 14. Multiples of the mean anomalistic month

Na, f. 19r: Tabula brevis Nu, f. 23v: Brevis tabula Va, f. 190v: Tabula brevis Ed. 1495, f. b7v: Tabula brevis Ed. 1526, f. 15v: Tabula brevis

The five columns in this table are the same as in Table 12, but in this case we are only given entries for the first four multiples of the mean anomalistic month: see Table 14. The purpose of this table is to facilitate computation, and it is used when the accumulated entries for collected years, expanded years, months, days, etc. exceed one or more anomalistic months, which then have to be subtracted (thus, the heading minue); see the worked example in our comments to Table 17, below. This is one of many instances where Bianchini pays special attention to finding the time when the mean anomaly is 0°. As was the case in the Tables 12 and 13, Regiomontanus omitted the column for the argument of lunar latitude.

Table 14: Multiples of the mean anomalistic month
0 0

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