﻿236 
  Scientific 
  Intelligence. 
  

  

  erences. 
  All 
  figures 
  are 
  classified 
  by 
  regions 
  and 
  also 
  by 
  sub- 
  

   jects. 
  All 
  references 
  are 
  classified 
  by 
  locality, 
  by 
  subject, 
  and 
  

   by 
  author. 
  

  

  The 
  writing 
  of 
  the 
  Face 
  of 
  the 
  Earth 
  covered 
  the 
  last 
  forty 
  

   years 
  of 
  Suess' 
  life. 
  The 
  part 
  included 
  in 
  the 
  present 
  issue 
  was 
  

   written 
  in 
  his 
  old 
  age, 
  but 
  shows 
  a 
  youthful 
  power 
  of 
  incorpora- 
  

   tion 
  and 
  assimilation. 
  The 
  subject 
  matter 
  includes 
  the 
  following 
  

   parts. 
  First, 
  analyses 
  of 
  the 
  plans 
  of 
  mountain 
  systems 
  and 
  of 
  

   their 
  transverse 
  sections. 
  Considerable 
  space 
  is 
  given 
  to 
  the 
  

   newer 
  interpretation 
  of 
  the 
  Alps 
  and 
  of 
  other 
  mountain 
  systems 
  

   in 
  that 
  light. 
  Second, 
  the 
  interior 
  of 
  the 
  earth 
  and 
  the 
  nature 
  

   of 
  igneous 
  intrusion. 
  Third, 
  the 
  origin 
  and 
  arrangement 
  of 
  vol- 
  

   canoes. 
  Fourth, 
  a 
  geologist's 
  studies 
  of 
  the 
  moon. 
  Fifth, 
  rela- 
  

   tions 
  of 
  density 
  to 
  continental 
  relief. 
  Sixth, 
  contraction 
  of 
  the 
  

   earth's 
  body. 
  Seventh, 
  a 
  concluding 
  chapter 
  on 
  life, 
  the 
  strand, 
  

   appearance 
  of 
  placental 
  mammals, 
  asylums. 
  j. 
  b. 
  

  

  7. 
  New 
  graphic 
  method 
  for 
  determining 
  the 
  depth 
  and 
  thick- 
  

   ness 
  of 
  strata 
  and 
  the 
  projection 
  of 
  dip; 
  by 
  Harold 
  S. 
  Palmer, 
  

   Prof. 
  Paper 
  120— 
  G, 
  pp. 
  121-129, 
  figs. 
  15-19, 
  pis. 
  XIV-XVI, 
  

   U. 
  S. 
  Geol. 
  Survey, 
  1918 
  — 
  This 
  paper 
  brings 
  out 
  very 
  simple, 
  

   rapid, 
  and 
  usable 
  methods 
  for 
  finding 
  the 
  solutions 
  of 
  these 
  con- 
  

   stantly 
  recurring 
  and 
  troublesome 
  questions. 
  For 
  example 
  let 
  

   the 
  dip 
  of 
  a 
  bed 
  be 
  A. 
  Let 
  the 
  strike 
  of 
  the 
  bed 
  make 
  an 
  angle 
  

   B 
  with 
  a 
  vertical 
  section 
  plane. 
  What 
  will 
  be 
  the 
  dip 
  C 
  of 
  the 
  

   bed 
  as 
  shown 
  on 
  the 
  section 
  plane? 
  The 
  formula 
  is 
  tan 
  C=tan 
  

   A 
  sin 
  B. 
  Where 
  many 
  examples 
  of 
  this 
  nature 
  recur, 
  trig- 
  

   onometric 
  solutions 
  by 
  means 
  of 
  logarithmic 
  tables 
  become 
  tedi- 
  

   ous, 
  gross 
  errors 
  are 
  easily 
  made, 
  and 
  the 
  proper 
  formula 
  must 
  

   be 
  ascertained 
  for 
  each 
  variant 
  of 
  these 
  problems. 
  Some 
  useful 
  

   diagrams 
  have 
  been 
  published 
  for 
  the 
  graphic 
  solution, 
  but 
  the 
  

   present 
  are 
  notable 
  for 
  their 
  simplicity 
  and 
  elegance. 
  Three 
  

   parallel 
  lines 
  are 
  graduated 
  in 
  the 
  proper 
  manner 
  in 
  each 
  of 
  

   the 
  three 
  plates. 
  These 
  lines 
  are 
  named. 
  For 
  instance, 
  in 
  the 
  

   case 
  previously 
  cited, 
  the 
  three 
  lines 
  represent 
  the 
  dip, 
  the 
  pro- 
  

   jected 
  dip, 
  and 
  the 
  angle 
  of 
  projection. 
  A 
  straight 
  edge 
  is 
  laid 
  

   across 
  these 
  graduated 
  lines 
  so 
  that 
  it 
  intersects 
  the 
  two 
  known 
  

   factors 
  at 
  the 
  proper 
  points. 
  The 
  answer 
  is 
  then 
  read 
  off 
  on 
  

   the 
  third 
  line 
  at 
  the 
  intersection 
  with 
  the 
  straight 
  edge. 
  

  

  The 
  method 
  depends 
  upon 
  a 
  principle 
  related 
  to 
  that 
  of 
  the 
  

   slide 
  rule. 
  The 
  graduations 
  of 
  the 
  lines 
  are 
  proportional 
  to 
  

   logarithms 
  and 
  the 
  lines 
  are 
  so 
  arranged 
  that 
  the 
  intercept 
  on 
  

   one 
  is 
  equal 
  to 
  the 
  sum 
  or 
  difference 
  of 
  the 
  logarithms 
  on 
  the 
  

   other 
  two, 
  but 
  the 
  reading 
  of 
  the 
  answer 
  gives 
  the 
  product 
  of 
  

   two 
  functions 
  direct 
  and 
  avoids 
  all 
  use 
  of 
  logarithmic 
  tables. 
  

   Every 
  scientist 
  should 
  understand 
  and 
  be 
  able 
  to 
  adapt 
  to 
  his 
  

   own 
  uses 
  this 
  very 
  ingenious 
  method. 
  j. 
  b. 
  

  

  8. 
  Osteology 
  of 
  the 
  Armored 
  Dinosauria 
  in 
  the 
  U. 
  8. 
  National 
  

   Museum, 
  with 
  special 
  reference 
  to 
  the 
  Genus 
  Stegosaurus; 
  U. 
  S. 
  

  

  