XXVI Congreso Internacional de Americanistas

de c rca~;ngly so tovvarJ tbe front. Tbe outer surfaces, always exposcd.
but 110t to the fire, were hard.
Tbe lintel was not only cracked in two, but its lower side was soft
and badly scaled except at the ends, which rested on tbe jambs. Its
exposeJ inner edge '\Vas 50ft and calcineJ, its outer edge black, as ii
with 5moke which had escaped from the entrance. This surface was
hard, as \'vas the topo
Stone wor i~ behilld the rear sherd wall \vas hard, and so, of course ,
\
\
\
\
... - - - -
Fig. 2.-Structure P-7. Piedras Negras. Cross-section and Elevation through
sunken passage.
were the sherds. But the mortar betweén tbern was very soft and
chalky.
No definite floor sl1rface could be identified within the fire-chamber,
thol1gh this was in good condition outside. There was, however, an illdeterminate
layer of soft gray powder, which could not be distinguished
from remains of mortar fallen from the walis .
• Dr. Mason encol1ntered similar conditions in the fire-cbamber of
Strl1cture P-7. In Struclures J-17 and S2 the writer failed to note
evidences of fire, but he was not on the lookout for them. They may
yet be found in Structure S-2. The very fact that he was able to c.'>:cavate
the interior of J-17, including its sunken pa ssage, without noting any
remains of such a chamber as this, makes it highly probable tbat itwas
very badly fire-cracked. The N -1 fire-chamber could not have been
properly excavated without the most careful and constant sl1pervision,
wbich was missing in tbe J-17 excavation two years before.
It is difficult to avoid the conclusion that tbe fire-chamber and the
sl1nken passage leading to it belong together and that the former is the
hearl of the whole complexo It seems highly probab:e that it will appear
in the remaining four central chambers whose interiors are entirely
l1nkown, in the form of a rectangular box-like masonry construction with
narrow low opening or doorway at the front.
Large quantities of heavy potshercls, otherwise jnexplicab~e, were