The temperature distribution and the heat flux across a cylinder and sphere are examined for steady state conditions of energy supply. The solutions for the cylinder are very similar to those for the sphere. This mathematical approach simulates the behavior of a statue represented in this way, when lighted for some hours in an exhibition room. The problem is important since many delicate objects are exposed to intense light for many hours each day, and deterioration processes may always act in the same manner. The side exposed to the light experiences not only the largest energy supply, but also the greater temperature gradient. In the objects with high water vapor content, the temperature gradient starts the migration of moisture, and is eventually responsible, together with the temperature variations, for severe deterioration of works of art. As a consequence, diffuse lighting in exhibition rooms is suggested. -- AATA