Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-05-16
ANCIENT j. S. DATES
!. SOUGHT IN TIMBER
Geographic Society Experts
Study Tree Rings for Cal
endar of New Mexico.

Intent on writing the final chapter
of d scientific detective story" Mel
M. Judd, archeologiSt, has just left
Washington for New Mexico to carry
on researches for the National Geo.
graphic Society into the life of some
of the earliest civilized residents OF the
United States.
DIR. Judd and other scientists sci
themselves the task several years age
of learning all that they could OF the
early occupants of the then ruined
Pueblo Bonito, a huge communal dwell
ing in the northwestern corner OF New
Mexico, which has been dubbed Amer
icas first apartment house" Many de-
tails have been disclosed of the lie
of the $500 occupants OF this grea'
structure in the days long before the
discovery of the New World, but tne
exact period during which the httle
city under one roof throbbed Win ac-
tivity remained unknown.
The researches of the National Geo
graphic Society came to be directed 10
the solution of this particular proolem'
Archaeology, botany, astronomy, micro
photography and plain "sleuthmg nave
been called into play. The trail mas leo
To the tree rings OF the oloer Iees
of the Southwest and to the similar
rings found in old beams taken from
the ruins of Pueblo Bonlto:
Growing trees deposit ring LOT eacu
year of their lives, and under micro
scope each ring shows inolVloual cIlal
acteristics. Moreover, in trees tnat nave
crown in the same region and so nave
been subjected to the same cycle OF
drv normal, and moist years, the rings
in different trees. deposited the same
wear. can be identified. Thus each tree
is a calendar for it's life span.
Trees Provide Calendar.
The life of one tree in New Mexico
viii not span many centuries. But an
old tree and a young one growing Sloe
bv side will record the same character
istic season, and the young tree VIII
carry on the record centuries after us
elder neighbor has fallen or has peer
cut for timber. BY taking cross-sec-
tions of both trees. perfect calendar
can be constructed for approximately
double the life-span of single tree.
Cross-sections or cores have been
made from many old beams taken
from ruined pueblos scattered over
Northern New Mexico, and their ring
records have been pieced together
with those from trees. In this way a
perfect calendar has been extended
backward without break from today
to 1860 AID. The beams from Pueblo
Bonito alone cover period OF 1uu
years. But between this series Of rings
and the modern series is gap OF I'M
known extent. but believed to be short.
It is on the work of closing this gap
that the present researches are being
conferred.
In seeking to close the gap, the
scientists are faced with task that
calls for even greater ability as detec-
tives than their past activities. During
-"the gap' the ancestors of the Hopi
Indians lived in the open rather than
In caves and cliff dwellings. Conse-
quently beams of that period will have
had no protection, and in most cases,
reached by the moisture from ram
and snow, will have rotted away.
Traced in Charred Wood.
The only chance of success is to dis
cover a ruined pueblo of the period
which was destroyed by fire, either ac-
cidentally or by enemies. Charred
beams will be preserved in spite OF
moisture, and even if they have been
converted entirely to charcoal, the
greatly desired ring record can still pc
read. If such charred beams can be
uncovered this Summer the date OF the
erection of Pueblo Lenito can be set
down as accurately as the building of
Sancta Sophia or the Colosseum or any
of the other structures that we have
knowledge of because of an unbroken
record of written history. Ruined
pueblos of the gap period have re-
Gently been discovered by means OF the
known gap pottery" and the work OF
this Summer will be concentrated on
these ruins. Only timbers cut before
1875 will be sought-beams from trees
that were felled when the Crusades were
still in progress, and when Marco Poio
was wandering over Asia.
The work Of piecing together Amer
ica's unique tree-ring calendar has LED
into laboratories and workshops as
well as into the desert. DR.. A. E.
Douglass, astronomer Of the University
of Adizona, was first to discover the cor
relation between sun-spot periods and
tree rings, and has been tireleSs in
building up the ring calendar He
has invented several instruments for
use in the work, including bit which
win. remove a core from a beam while
1t remains in a building. and cameras
which take highly magnified photo
graphs of rings. Other scientists who
have worked with DR.. Judd and DR..
Douglass are DR. H2rold S. Cotton,
director of the Museum of Northern
Arizona, at Flagstaff. and Lyndon Har-
grave of the same institution. All have
had to play the parts of diplomats as
well as scientists and detectives. Many
Of the beams from which cores have
been desired were found in chambers
which the Indians consider holy.