﻿246 
  Scientific 
  Intelligence. 
  

  

  12. 
  Discharge 
  rays 
  and 
  the 
  connection 
  between 
  them 
  and 
  the 
  

   Cathode 
  and 
  Rontgen 
  rays. 
  — 
  M. 
  Willibad 
  Hoffmann 
  has 
  studied 
  

   the 
  luminescence 
  produced 
  in 
  various 
  substances 
  by 
  means 
  of 
  

   electric 
  discharges 
  of 
  various 
  forms 
  and 
  has 
  traced 
  the 
  phenomena 
  

   from 
  its 
  beginning 
  in 
  air 
  to 
  its 
  manifestation 
  in 
  rarified 
  media. 
  — 
  

   Ann. 
  der 
  Physik 
  and 
  Chemie, 
  No. 
  2, 
  1897, 
  pp. 
  269-299. 
  j. 
  t. 
  

  

  13. 
  Large 
  storage 
  battery. 
  — 
  Professor 
  Trowbridge 
  has 
  had 
  con- 
  

   structed 
  a 
  storage 
  battery 
  of 
  ten 
  thousand 
  cells 
  for 
  the 
  Jefferson 
  

   Physical 
  laboratory. 
  The 
  details 
  of 
  the 
  battery 
  have 
  been 
  com- 
  

   pleted 
  with 
  great 
  skill 
  by 
  the 
  mechanician, 
  Mr. 
  G. 
  M. 
  Thompson. 
  

   The 
  battery 
  gives 
  a 
  voltage 
  of 
  at 
  least 
  twenty 
  thousand, 
  with 
  a 
  

   current 
  of 
  eight 
  amperes. 
  It 
  is 
  unable 
  to 
  light 
  a 
  Crookes 
  tube. 
  

   The 
  lowest 
  voltage 
  which 
  will 
  satisfactorily 
  produce 
  the 
  Rontgen 
  

   rays 
  appears 
  to 
  be 
  one 
  hundred 
  thousand 
  volts. 
  The 
  battery 
  can 
  

   be 
  employed 
  with 
  great 
  success 
  to 
  charge 
  Leyden 
  jars 
  in 
  parallel 
  

   and 
  to 
  discharge 
  them 
  in 
  series. 
  A 
  small 
  electric 
  motor 
  is 
  

   employed 
  to 
  revolve 
  a 
  suitable 
  commutator 
  in 
  order 
  to 
  discharge 
  

   the 
  Leyden 
  jars 
  rapidly 
  in 
  series. 
  The 
  apparatus 
  is 
  a 
  modifica- 
  

   tion 
  of 
  that 
  first 
  used 
  by 
  Plante. 
  It 
  enables 
  one 
  to 
  study 
  quanti- 
  

   tatively 
  the 
  high 
  electromotive 
  force 
  necessary 
  to 
  produce 
  the 
  

   Rontgen 
  rays. 
  An 
  oscillatory 
  discharge 
  of 
  electricity 
  through 
  a 
  

   Crookes 
  tube 
  appears 
  to 
  be 
  prejudicial 
  for 
  the 
  development 
  of 
  

   the 
  X-rays. 
  The 
  best 
  results 
  are 
  obtained 
  without 
  a 
  condenser 
  in 
  

   series 
  with 
  the 
  Crookes 
  tube. 
  This 
  seems 
  to 
  show 
  that 
  the 
  elec- 
  

   trostatic 
  polarization 
  is 
  largely 
  instrumental 
  in 
  the 
  generation 
  of 
  

   the 
  Rontgen 
  rays. 
  j. 
  t. 
  

  

  14. 
  Outlines 
  of 
  Electricity 
  and 
  Magnetism 
  ; 
  by 
  Charles 
  A. 
  

   Perkins. 
  277 
  pp. 
  New 
  York, 
  1896 
  (Henry 
  Holt 
  & 
  Company). 
  

   — 
  The 
  author 
  has 
  presented 
  in 
  this 
  little 
  volume 
  the 
  prominent 
  

   phenomena 
  and 
  principles 
  of 
  electricity 
  and 
  magnetism. 
  Further, 
  

   he 
  has 
  attempted, 
  and 
  in 
  the 
  main 
  with 
  success, 
  to 
  show 
  how 
  

   modern 
  theories 
  serve 
  to 
  explain 
  the 
  observed 
  phenomena 
  and 
  to 
  

   bring 
  out 
  the 
  essential 
  relation 
  between 
  them. 
  Numerous 
  illustra- 
  

   tions 
  and 
  analogies 
  are 
  employed 
  and 
  in 
  general 
  in 
  such 
  a 
  way 
  as 
  

   to 
  materially 
  aid 
  the 
  elementary 
  student 
  to 
  obtain 
  clear 
  ideas 
  of 
  

   the 
  subjects 
  under 
  discussion. 
  

  

  II. 
  Geology 
  and 
  Mineralogy. 
  

  

  1. 
  Principal 
  features 
  of 
  the 
  Geology 
  of 
  Southeastern 
  Washing- 
  

   ton 
  ; 
  by 
  Israel 
  C. 
  Russell. 
  (Abstract 
  furnished 
  by 
  the 
  author.) 
  

   —The 
  following 
  note 
  gives 
  a 
  brief 
  statement 
  of 
  the 
  results 
  of 
  a 
  

   six-weeks 
  reconnoissance 
  in. 
  the 
  southeastern 
  portion 
  of 
  the 
  State 
  

   of 
  Washington 
  made 
  for 
  the 
  U. 
  S. 
  Geological 
  Survey. 
  

  

  Practically 
  all 
  of 
  that 
  portion 
  of 
  Washington 
  which 
  lies 
  south 
  

   of 
  the 
  Big 
  Bend 
  of 
  the 
  Columbia 
  is 
  occupied 
  by 
  a 
  succession 
  of 
  

   basaltic 
  lava 
  flows. 
  This 
  is 
  a 
  portion 
  of 
  a 
  vast 
  lava-covered 
  

   region 
  embracing 
  northern 
  California, 
  central 
  and 
  eastern 
  Oregon, 
  

   central 
  and 
  southeastern 
  Washington 
  and 
  southern 
  Idaho. 
  The 
  

   great 
  fissure 
  eruptions 
  which 
  supplied 
  the 
  Columbia 
  lava, 
  as 
  the 
  

   basalt 
  is 
  termed, 
  occurred 
  in 
  the 
  Miocene. 
  

  

  