Tibaldo and the Hole in the Calendar

Tibaldo Bondi, son of the assistant to the famous Bolognese physician Turisanus, is supposed to celebrate his 12th birthday in 1582. But 1582 is no ordinary year. Inaccuracies in the calendar established under Julius Caesar have been piling up for over a millennium, causing Easter to drift out of its traditional season. When Pope Gregory XIII decrees a long-needed calendar reform, part of the correction involves dropping ten days from the month of October, including October 10th, Tibaldo's birthday. This story cleverly weaves an enjoyable account of the cultural and scientific milieu of 16th century Italy. Through Tibaldo's eyes we learn of contemporary medical skills as practiced by his sister, a midwife, and his father; from Tibaldo's schoolteachers we learn about Renaissance astronomy and other sciences; and of course we learn the basis of the Gregorian reform that led to the calendar we use, with just minor changes, to this day.

From The Publisher:

Tibaldo and the Hole in the Calendar is the story of how an eleven-year old boy growing up in 16th century Italy loses his birthday when the Gregorian calendar replaces the Julian calendar in 1582, and how he fights to prevent this loss. The author cleverly weaves elements of the cultural and scientific milieu of his time into an engaging and intelligent tale. Tibaldo's father is a medical assistant, and his sister is a midwife. He grows up learning about current medical practices by watching his father and sister and by listening to the great Professor Turisanus, for whom his father works. Tibaldo is fascinated by medicine and proves himself to be a fast learner, quickly gaining the respect of Professor Turasanus, who becomes a mentor for Tibaldo and sends him to the very best of schools. However, when Tibaldo learns that the Julian calendar is about to be revised, he realizes that he is about to lose his 13th birthday and determines to do something about this. The result is amusing and informative.