Harvard’s Fogg Museum, a Colonial Revival building at 32 Quincy Street, reopened five years ago after Renzo Piano’s major expansion, or “reboot” as The Guardian called it. The other day I had a free hour and I spent it in the Calderwood Courtyard of the old/new building. The architect of the original museum, Charles Coolidge of Coolidge, Shepley, Bulfinch and Abbot (H.H. Richardson’s successor firm), modeled the cloister-like arcades on the loggia of a sixteenth-century canon’s house in Montepulciano, designed by Antonio da Sangallo the Elder. Admittedly, the modeling is very loose, more like a stylized memory, and has a kind of American crispness in execution that is very different from the original. Piano added two stories on top of the arcade making a sort of spumoni—modern above, Renaissance below. The modernist layer is thin fare; Piano’s work, with its fussy greenhouse roof, looks provisional, like a temporary addition. I came to the conclusion that there were three chief reasons. 1) Steel and glass are simply not as engaging as travertine. 2) The orders of the arcades play with scale; the anonymous minimalist addition is more like utilitarian engineering—nothing but the facts ma’am. 3) The modeled arcades are defined by sharp shadows; Piano’s addition, which is mostly glass, contains no shadows. If architecture is indeed the “the masterly, correct and magnificent play of volumes brought together in light,” then the addition is not architecture at all. In the old arcades, our glance is caught by the details of the Ionic and Doric capitals; in the new addition there are no details (except for the lighting fixtures), and we quickly loose interest. Almost 400 years separate Coolidge’s work from that of Sangallo; less than 90 years later, Piano comes along and and it’s all gone.