Right at the dawn of "craftsmanship" [c.2550BC], was erected the Great Pyramid at Giza. 1000 tons of cut white-limestone blocks were hauled up every day for 16 years during the construction. In the central chamber, intended for King Khufu's [2606BC - 2584BC] sarcophagus, the 'roof' [ie the top-half of the pyramid!] was supported on massive 50 ton slabs of granite hauled up from Aswan. 5 of these had been exactly inched into place, when one of them developed a small crack, due to excessive bending stress. To reduce the load imposed on this beam, Khufu's "engineer" laid further sets of similar slabs over the first, 4 layers in all, then over that an angled layer to direct force to outside of the slab-beam assembly. A 'laminated beam', built 4500 years ago. And, it's got holes in it!, in the form of 3 ft crawlspaces beween the layers. This whole remarkable structure was not exceeded in height until the Eiffel Tower was built in the 1880s, even though literally millions of 2-ton limestone outer casing blocks were robbed-out to build Cairo in the Middle Ages.
Alan
