MORGAN. ] UNREMOVED CORE FOUND IN A STRUCTURE. 267 
latter had seasoned and settled. It tends to show that with small stones 
of the size used, about a foot long and six inches thick, the triangular 
ceiling as it projected toward the center in rising, required the interior 
support of a core to insure the possibility of construction by their methods. 
Once put together over such a core and carried up several feet above the top 
of the arch, the down weight of the superincumbent mass would articulate 
and hold the masonry together. It shows further that the essential feature 
of the arch is wanting in this contrivance. 
The proof of this assertion is found in the actual presence of the unre- 
moved core in one of these edifices in all of its apartments. Mr. Stephens 
found every room of the back building on the second terrace filled with 
masonry from bottom to top, left precisely as it was when the building was 
finished. He remarks that ‘the north half of the second range has a curious 
and unaccountable feature. It is called thé Casa Cerrada, or ‘closed house,’ 
having ten doorways, all of which are blocked up on the inside with stone 
and mortar. * * * In front of several were piles of stones which they 
[his workmen] had worked out from the doorways, and under the lintels 
were holes through which we were able to crawl inside; and here we found 
ourselves in apartments finished with walls and ceilings like all the others, 
but filled up, except so far as they had been emptied by the Indians, with 
solid masses of mortar and stone. There were ten of these apartments in 
all, two hundred and twenty feet long and ten feet deep, which thus being 
filled up made the whole building a solid mass; and the strangest feature 
was that the filling up of the apartments must have been simultaneous with 
the erection of the buildings; for, as the filling in rose above the tops of the 
doorways, the men who performed it never could have entered to their work 
through the doors. It must have been done as the walls were built, and 
the ceiling must have closed over a solid mass.”* 
It does not seem to have occurred to Mr. Stephens that the masonry 
within each room was a core, without which a vaulted chamber in this form 
could not have been constructed with their knowledge of the art of build- 
ing. It shows the rudeness of their mechanical resources as well as the 
real condition of the art among them, but at the same time increases our 
1Incidents of Travel, ete., ii, 22. 
