﻿66 
  Scientific 
  Intelligence. 
  

  

  These 
  physical 
  and 
  chemical 
  correspondences 
  justify, 
  I 
  think, 
  

   the 
  conclusion 
  that 
  in 
  the 
  Welland 
  siderolite 
  there 
  are 
  but 
  two 
  

   distinct 
  nickel-iron 
  alloys, 
  viz: 
  kamacite 
  and 
  tsenite; 
  and 
  that 
  

   the 
  so-called 
  plessite 
  is 
  merely 
  thin 
  alternating 
  lamellae 
  of 
  

   kamacite 
  and 
  tsenite. 
  

  

  It 
  is 
  unsafe 
  to 
  generalize 
  on 
  a 
  single 
  analysis, 
  but 
  an 
  exami- 
  

   nation 
  of 
  the 
  markings 
  of 
  other 
  meteoric 
  irons 
  suggests 
  the 
  

   thought 
  that 
  in 
  them 
  also 
  there 
  may 
  be 
  but 
  two 
  distinct 
  alloys. 
  

   Such 
  are 
  the 
  Descubridora, 
  the 
  Glorietta 
  Mi 
  and 
  notably 
  the 
  

   Kiowa 
  Co. 
  and 
  the 
  Augusta 
  Co., 
  Va. 
  meteorites. 
  In 
  sections 
  

   of 
  the 
  last 
  two 
  irons 
  in 
  Ward 
  & 
  Howell's 
  collection 
  every 
  piece 
  

   of 
  the 
  so-called 
  plessite 
  in 
  the 
  Augusta 
  Co. 
  iron 
  shows 
  its 
  thin 
  

   lamellae, 
  and 
  in 
  the 
  Kiowa 
  Co. 
  pallasite 
  the 
  gradations 
  of 
  the 
  

   markings 
  are 
  such, 
  that 
  in 
  parts 
  of 
  the 
  iron 
  it 
  wonld 
  be 
  difficult 
  

   to 
  say 
  which 
  should 
  be 
  called 
  kamacite 
  and 
  which 
  plessite. 
  

  

  In 
  etching 
  meteoric 
  iron, 
  the 
  kamacite 
  is 
  attacked 
  by 
  acid 
  

   more 
  readily 
  than 
  the 
  teenite 
  richer 
  in 
  nickel. 
  The 
  tsenite 
  and 
  

   plessite 
  stand 
  in 
  relief. 
  Where 
  lamellae 
  do 
  not 
  show 
  in 
  plessite 
  

   may 
  not 
  closely 
  crowded 
  taenite 
  bands 
  have 
  protected 
  neighbor- 
  

   ing 
  kamacite 
  layers 
  from 
  acid 
  action, 
  and 
  might 
  not 
  more 
  care- 
  

   ful 
  or 
  prolonged 
  etching 
  develop 
  lines 
  in 
  plessite 
  that 
  now 
  

   appear 
  homogeneous 
  ? 
  

  

  Reynolds 
  Laboratory, 
  

   University 
  of 
  Rochester, 
  April, 
  1891. 
  

  

  SCIENTIFIC 
  INTELLIGENCE. 
  

  

  I. 
  Chemistry 
  and 
  Physics. 
  

  

  1. 
  On 
  the 
  Speed 
  of 
  the 
  Explosive 
  leave 
  in 
  Solid 
  and 
  Liquid 
  

   Bodies. 
  — 
  Berthelot 
  has 
  studied 
  the 
  phenomena 
  attending 
  the 
  

   production 
  and 
  transmission 
  of 
  the 
  explosive 
  wave 
  in 
  solid 
  and 
  

   liquid 
  substances 
  and 
  finds 
  that 
  these 
  phenomena 
  do 
  not 
  have 
  

   the 
  regularity 
  of 
  progression 
  observed 
  in 
  gases. 
  In 
  liquids 
  the 
  

   speed 
  appears 
  to 
  be 
  dependent 
  upon 
  the 
  rigidity 
  of 
  the 
  enclosing 
  

   tubes, 
  this 
  speed 
  being 
  the 
  greater 
  the 
  greater 
  the 
  resistance 
  of 
  

   the 
  tubes 
  to 
  rupture. 
  It 
  is 
  probably 
  not 
  possible, 
  however, 
  to 
  

   prepare 
  tubes 
  which 
  can 
  bear 
  without 
  fracture 
  the 
  force 
  of 
  the 
  

   explosion, 
  since 
  the 
  volume 
  of 
  the 
  high 
  explosives 
  is 
  smaller 
  as 
  a 
  

   rule 
  than 
  the 
  volume 
  of 
  their 
  decomposition 
  products, 
  even 
  when 
  

   these 
  are 
  compressed 
  into 
  the 
  liquid 
  condition. 
  In 
  methyl 
  nitrate, 
  

   the 
  author 
  finds 
  that 
  the 
  explosion 
  travels, 
  when 
  the 
  liquid 
  is 
  

   contained 
  in 
  tubes 
  of 
  steel, 
  with 
  a 
  speed 
  of 
  about 
  2100 
  meters 
  per 
  

   second. 
  — 
  C. 
  It., 
  cxii, 
  16 
  ; 
  Ber. 
  Berl. 
  Chem. 
  G-es., 
  xxiv, 
  (Ref.) 
  253, 
  

   April, 
  1891. 
  G. 
  f. 
  b. 
  

  

  2. 
  On 
  the 
  Relation 
  betioeen 
  the 
  Electrical 
  Energy 
  and 
  the 
  

   Chemical 
  Energy 
  in 
  Voltaic 
  cells. 
  — 
  A 
  series 
  of 
  experiments 
  by 
  

   Levay 
  has 
  been 
  made 
  to 
  ascertain 
  the 
  amount 
  of 
  heat 
  srener- 
  

  

  