KEEPING WARM 
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ARCHEOLOGY TOUR TO MEXICO January 11-29, 1982 
ANCIENT MAYA ARCHEOLOGY February 1-18, 1982 
Discover the ancient civilizations and archeology of pre-Columbian Mexico 
and the Maya world with the American Museum's C. Bruce Hunter. Sites on 
the Mexican tour include Mexico City, Cuicuilco, El Tajin, Jalcipa, Cholula, 
Teotihuacan, Tula, Oaxaca. Mitla, Monte Alban, Cuernavaca, Xochicalco and 
Taxco The Maya tour includes visits to Merida, Dzibilchaltun, Chichen Itza, 
Tulum, La Venta, Palenque, Edzna, Uxmal, Sayil, Xlapak and Labna. Tours 
include colonial towns, museums and the finest accommodations, and are 
limited to 18 participants. C. Bruce Hunter is Lecturer in Archeology at the 
American Museum, and author of A Guide to Ancient Mexican Ruins and 
a Guide to Ancient Maya Ruins. For further information write to DISCOVERY 
TOURS, American Museum of Natural History, Central Park West at 79 St., 
NY NY 10024, or call (212) 873-1440. 
to the warming of room air. (Our Heat- 
ilator was a metal firebox in lieu of a 
traditional brick lining. Openings faced 
the room on each side at floor level and 
above the fireplace. Fans installed be- 
hind the lower openings sucked cold air 
in from the floor and blew warmed air 
back into the room from the top open- 
ings.) The contributions to heat gain 
from a fireplace, however, are more or 
less offset by the loss of room air that is 
drawn up the flue. The warmed air is 
replaced by cold outside air that enters 
through cracks anywhere in the house. 
This effect cannot be prevented — a 
house that is airtight except for its flue 
cannot support a functional fireplace 
and will fill with smoke. Thus some 
fireplaces actually cause the average 
house temperature to fall when they are 
in operation. To alleviate this, at least in 
part, it is good practice to provide a 
source of outside air at a point near the 
fireplace. 
Fireplaces are most efficient when 
the damper is as nearly closed as it can 
be without creating a pall of smoke, but 
even then they are not remarkably effi- 
cient. Some improvement can be 
achieved by covering the front of the 
fireplace. Glass doors with control vents 
are available for this purpose. 
In an effort to improve the efficiency 
of our fireplace, I hung steel plates over 
the front from pegs welded to the top. 
Similar to glass doors but much less 
costly, these noticeably reduced the 
draft and provided a measure of safety 
at night when the fire was left burning 
but unattended. Nevertheless, the burn- 
ing rate required to maintain a comfort- 
able temperature was reduced only 
about 25 percent. Furthermore, the 
plates were inconvenient because one of 
them had to be removed in order to add 
wood, and I was apprehensive that a 
malfunction in the Heatilator fans 
might allow the firebox temperatures to 
rise to dangerous levels. So the plates 
were used with caution. 
Finally I decided to remove the entire 
fireplace and replace it with an airtight, 
cast-iron, wood-burning stove. This en- 
tailed a great deal of work, considerable 
additional cost, and made a mess in the 
living room. Our beautiful corner fire- 
place and chimney were dismantled 
brick by brick, but we now have ap- 
proximately 1,000 clean bricks awaiting 
another use. 
We think we did the right thing. With 
less than half as much wood, our cast- 
iron stove provides more effective heat 
106 
