Mathematical Garden

Whose month a lunation becomes.

30 days, another 29. A lunation of even days is attributed to an odd month, and vice-versa, whence the verse:

An odd Moon for an even, an even for an odd month.

Among us, however, a lunation is always said to be of that month in which it ends, whence the verse:

Let the lunation be given to the month in which it is completed.

If, however, two lunations end in one month, the middle one will be intercalary, and the other following it will be assigned to the following month, as we will explain below in chapter 4 of the second treatise.

On the wanderings or mansions. Chapter 10. Of the Moon in the year 1552, examined with my teacher, the most excellent mathematician Petrus Pitatus.

After it has been spoken of regarding the various accidents of the Moon, it seems to me fitting to treat here of its mansions. That the wanderings of the Moon, which astrologers call mansions, are 28, escapes no one, for it traverses the whole zodiac in almost as many days: from which it happens that each one encompasses 12 degrees and 51 minutes and 26 seconds. The beginnings of which, rectified to this our time by the most excellent Petrus Pitatus my teacher, as well as the qualities, properties, and utilities of the same, I have been pleased to collect for this our little work. While, therefore, the Moon, being well affected, progresses through the first mansion, as for example from the 20th part of Aries up to the 3rd of Taurus, they hold it to be a useful and suitable time to use purgative potions and to undertake journeys.

But if, in this wandering, a conjunction or eclipse of the Luminaries is celebrated, they have handed down that it is inconvenient for all things, and thus it is to be observed in the remaining mansions of the Moon.