Have they found the lost Leonardo? Giorgio Vasari (1511-74) may have built a wall covering up a fresco by da Vinci to paint his own, cherished fresco in Florence’s Palazzo Vecchio. Leonardo was reputedly experimenting with his materials when he painted this ‘missing’ fresco, so not much of it may survive. Thermographic evidence may be brought to bear to ascertain its exact nature and location. If it appears to be intact, should the Vasari be razed to access it?