Recently, researchers were studying what they think is da Vinci’s earliest-known artwork. They used special lighting to study the work and discovered there were two images, not one. One drawing was on the back of the piece, which is dated August 5, 1473. The drawing on the front, made when Leonardo was 21 years old, shows a river valley and a castle outside the city of Florence. There is little left of the drawing on the back, perhaps because it was rubbed off. Only a bridge over a river can be seen. But there is writing on both sides. The writing on the front gives the date and goes from right to left. Some people would call this “mirror-writing.” Leonardo often wrote this way in his notebooks. On the back, the handwriting goes from left to right, and tells about an agreement, probably to produce a work of art. Cecilia Frosinini is an art historian. She said, “Leonardo was born left-handed, but was taught to write with his right hand from a very young age. By looking at his writings, including from this drawing, one can see his right-handed calligraphy is educated and well done.”