ABSTRACT
The Guastavinos called such shells ‘‘timbrel vaults’’, because they resounded like drums or tamborines when jumped upon or slapped. The Guastavinos were thus at pains to distinguish their shells from the classical, mediaeval style of vault, in which the component masonry blocks were full-thickness ‘‘voussoirs’’, with dry or weak-mortar interfaces. Although it may have been possible to advance the construction of mediaeval vaults without the use of much formwork, such vaults were less ‘‘cohesive’’—another term used frequently by the Guastavinos-than their own ‘‘timbrel’’ shells. Provided the Guastavino cement is strong enough, the two-or three-layer overlappingtile construction of their vaults is more akin to a heavy-duty layered composite than to a single-layer mosaic of voussoirs. And the shell behaves as an elastic continuum, as witnessed by the ‘‘timbrel’’ tones.
