﻿ANNUAL 
  RINGS 
  OF 
  TREES 
  — 
  DOUGLASS. 
  237 
  

  

  counting 
  to 
  the 
  last 
  growth 
  ring 
  of 
  each 
  it 
  was 
  easy 
  to 
  tell 
  the 
  

   relative 
  dates 
  at 
  which 
  the 
  various 
  timbers 
  were 
  cut. 
  

  

  In 
  order 
  to 
  help 
  in 
  describing 
  given 
  rings 
  in 
  these 
  various 
  sections, 
  

   a 
  purely 
  imaginary 
  date 
  was 
  assumed 
  for 
  a 
  certain 
  rather 
  large 
  

   ring 
  which 
  appeared 
  in 
  all 
  the 
  timbers. 
  This 
  was 
  called 
  E. 
  D. 
  

   (relative 
  date) 
  500, 
  and 
  all 
  other 
  rings 
  earlier 
  or 
  later 
  are 
  designated 
  

   by 
  this 
  system 
  of 
  relative 
  dates. 
  Many 
  interesting 
  results 
  were 
  evi- 
  

   dent 
  as 
  soon 
  as 
  the 
  various 
  relative 
  dates 
  were 
  compared. 
  In 
  the 
  

   first 
  place, 
  instead 
  of 
  requiring 
  many 
  hundreds 
  of 
  years 
  in 
  con- 
  

   struction 
  as 
  any 
  one 
  would 
  suppose 
  in 
  looking 
  at 
  the 
  ruin, 
  the 
  larger 
  

   part 
  of 
  it 
  was 
  evidently 
  erected 
  in 
  the 
  course 
  of 
  10 
  years, 
  for 
  

   the 
  dates 
  of 
  cutting 
  the 
  timbers 
  found 
  in 
  the 
  large 
  north 
  side 
  in- 
  

   clude 
  only 
  eight 
  or 
  nine 
  years. 
  The 
  earliest 
  timbers 
  cut 
  were 
  in 
  

   the 
  northeast 
  part 
  of 
  the 
  structure. 
  The 
  later 
  timbers 
  are 
  at 
  the 
  

   northwest, 
  and 
  it 
  is 
  evident 
  that 
  the 
  sequence 
  of 
  building 
  was 
  from 
  

   the 
  easterly 
  side 
  to 
  the 
  westerly 
  side, 
  ending 
  up 
  with 
  the 
  westerly 
  

   end 
  and 
  extending 
  toward 
  the 
  south. 
  

  

  In 
  one 
  place 
  beams 
  from 
  three 
  stories, 
  one 
  over 
  the 
  other, 
  were 
  

   obtained. 
  The 
  top 
  and 
  bottom 
  ceiling 
  timbers 
  were 
  cut 
  one 
  year 
  

   later 
  than 
  those 
  of 
  the 
  middle 
  ceiling, 
  showing 
  that 
  in 
  vertical 
  con- 
  

   struction 
  the 
  three 
  floors 
  were 
  erected 
  in 
  immediate 
  succession. 
  A 
  

   floor 
  pole 
  from 
  Pueblo 
  Bonito 
  was 
  cut 
  one 
  year 
  later 
  than 
  the 
  latest 
  

   beam 
  obtained 
  from 
  that 
  ruin. 
  

  

  An 
  even 
  more 
  interesting 
  fact 
  was 
  soon 
  after 
  disclosed. 
  A 
  study 
  

   of 
  the 
  art 
  and 
  industries 
  of 
  neighboring 
  ruins 
  had 
  satisfied 
  Mr. 
  Nel- 
  

   son 
  and 
  Mr. 
  Morris 
  of 
  the 
  American 
  Museum 
  that 
  some 
  of 
  the 
  

   ruins 
  in 
  Chaco 
  Canyon, 
  some 
  50 
  miles 
  to 
  the 
  south, 
  were 
  not 
  far 
  

   different 
  in 
  age 
  from 
  those 
  at 
  Aztec. 
  The 
  only 
  beams 
  immediately 
  

   available 
  from 
  the 
  Chaco 
  Canyon 
  ruins 
  had 
  been 
  collected 
  in 
  the 
  

   Pueblo 
  Bonito 
  ruin 
  25 
  years 
  before 
  by 
  the 
  Hyde 
  expedition. 
  Accord- 
  

   ingly 
  sections 
  were 
  cut 
  from 
  seven 
  beams 
  which 
  this 
  expedition 
  

   had 
  brought 
  back 
  to 
  New 
  York 
  City. 
  One 
  of 
  these 
  sections 
  was 
  a 
  

   cedar 
  and 
  has 
  not 
  yet 
  been 
  interpreted, 
  but 
  the 
  others 
  were 
  imme- 
  

   diately 
  identified 
  in 
  age 
  both 
  among 
  themselves 
  and 
  with 
  reference 
  

   to 
  the 
  Aztec 
  timbers. 
  It 
  was 
  found 
  that 
  these 
  Pueblo 
  Bonito 
  beams 
  

   were 
  cut 
  within 
  a 
  few 
  years 
  of 
  each 
  other 
  at 
  a 
  time 
  preceding 
  the 
  

   cutting 
  of 
  the 
  timbers 
  at 
  Aztec 
  by 
  40 
  to 
  45 
  years. 
  Many 
  of 
  the 
  

   timbers 
  of 
  each 
  ruin 
  were 
  living 
  trees 
  together 
  for 
  more 
  than 
  100 
  

   years 
  and 
  some 
  even 
  for 
  200 
  years, 
  and 
  there 
  seems 
  no 
  possible 
  

   doubt 
  of 
  the 
  relative 
  age 
  here 
  determined. 
  This 
  result 
  showing 
  

   that 
  a 
  Chaco 
  Canyon 
  ruin 
  was 
  built 
  nearly 
  a 
  half 
  century 
  before 
  

   Aztec 
  is 
  the 
  first 
  actual 
  determination 
  of 
  such 
  a 
  difference 
  in 
  exact 
  

   years. 
  A 
  single 
  beam 
  from 
  Pefiasco, 
  some 
  4 
  miles 
  down 
  the 
  Chaco 
  

   Canyon 
  from 
  Pueblo 
  Bonito 
  showed 
  that 
  its 
  building 
  was 
  interme- 
  

   diate 
  between 
  Pueblo 
  Bonito 
  and 
  Aztec. 
  

  

  