﻿64 
  JOURNAL 
  OP 
  THE 
  WASHINGTON 
  ACADEMY 
  OF 
  SCIENCES 
  VOL. 
  12, 
  NO. 
  3 
  

  

  carinal 
  lobe 
  linear-apiculate 
  and 
  longer. 
  Petals 
  white, 
  delicately 
  purple- 
  

   lined, 
  glabrous; 
  standard 
  strongly 
  reflexed, 
  ovate, 
  attenuate 
  at 
  the 
  base, 
  

   emarginate 
  at 
  the 
  apex, 
  the 
  claw 
  3 
  mm. 
  long, 
  the 
  blade 
  10 
  mm. 
  long, 
  8.5 
  mm. 
  

   broad; 
  wings 
  obovate, 
  oblique, 
  auriculate 
  on 
  the 
  vexillar 
  side, 
  the 
  claw 
  3.5 
  

   mm. 
  long, 
  the 
  blade 
  11.5 
  mm. 
  long, 
  4.5 
  mm. 
  broad; 
  carinal 
  petals 
  falcate, 
  

   auriculate 
  on 
  the 
  vexillar 
  side, 
  obtuse 
  at 
  the 
  apex, 
  the 
  claw 
  as 
  in 
  the 
  wings, 
  

   the 
  blade 
  about 
  10 
  mm. 
  long, 
  4 
  mm. 
  broad. 
  Stamens 
  10, 
  monadelphous, 
  

   alternately 
  long 
  and 
  short. 
  Pistil 
  about 
  13 
  mm. 
  long, 
  glabrous, 
  the 
  ovary 
  

   long-stipitate, 
  linear, 
  4 
  to 
  6-ovulate; 
  style 
  strongly 
  arcuate; 
  stigma 
  capitel- 
  

   late, 
  inconspicuous. 
  

  

  Type 
  in 
  the 
  U. 
  S. 
  National 
  Herbarium, 
  no. 
  577918, 
  collected 
  at 
  Nicoya, 
  

   Costa 
  Rica, 
  April, 
  1900, 
  by 
  A. 
  Tonduz 
  (no. 
  13969). 
  

  

  A 
  specimen 
  (Inst, 
  fis.-geogr. 
  n. 
  13887), 
  obtained 
  by 
  the 
  same 
  collector 
  from 
  

   the 
  forest 
  of 
  Nicoya, 
  is 
  probably 
  the 
  same 
  species. 
  However, 
  the 
  specimens 
  

   are 
  leafless 
  and 
  floral 
  panicles 
  larger 
  and 
  many 
  -flowered. 
  Mr. 
  Tonduz 
  says 
  

   that 
  the 
  tree 
  they 
  proceed 
  from 
  is 
  a 
  preponderant 
  one 
  in 
  the 
  forests 
  of 
  the 
  

   peninsula, 
  being 
  gregarious 
  and 
  giving 
  a 
  characteristic 
  bluish-gray 
  color 
  to 
  

   the 
  forests 
  in 
  April, 
  the 
  flowering 
  time. 
  

  

  The 
  affinities 
  of 
  this 
  species 
  are 
  evidently 
  with 
  Dalhergia 
  retusa 
  Hemsley. 
  

  

  EIvKCTRIClTY. 
  — 
  Electromotive 
  force 
  of 
  cells 
  at 
  low 
  temperatures.^ 
  

   G. 
  W. 
  ViNAL 
  AND 
  F. 
  W. 
  Altrup, 
  Bureau 
  of 
  Standards. 
  

  

  The 
  practical 
  importance 
  of 
  a 
  knowledge 
  of 
  the 
  electromotive 
  be- 
  

   havior 
  of 
  dry 
  cells 
  and 
  storage 
  batteries 
  at 
  low 
  temperatures 
  has 
  arisen 
  

   from 
  their 
  use 
  in 
  the 
  Arctic 
  and 
  at 
  high 
  altitudes. 
  In 
  June, 
  1921 
  the 
  

   Department 
  of 
  Terrestrial 
  Magnetism 
  of 
  the 
  Carnegie 
  Institution, 
  of 
  

   Washington, 
  through 
  Dr. 
  S. 
  J. 
  Mauchly, 
  requested 
  the 
  Bureau 
  of 
  

   Standards 
  to 
  furnish 
  information 
  in 
  answer 
  to 
  the 
  following 
  questions 
  : 
  

   (a) 
  What 
  is 
  the 
  open 
  circuit 
  voltage 
  of 
  dry 
  cells 
  at 
  approximately 
  0° 
  

   Fahrenheit 
  and 
  below? 
  (b) 
  Are 
  dry 
  cells 
  fit 
  for 
  use 
  after 
  they 
  have 
  

   been 
  frozen 
  and 
  thawed 
  out 
  again? 
  Since 
  there 
  was 
  no 
  reliable 
  in- 
  

   formation 
  available 
  on 
  this 
  subject, 
  experimental 
  work 
  was 
  under- 
  

   taken 
  which 
  included 
  observations 
  on 
  storage 
  batteries 
  also. 
  In 
  

   the 
  first 
  experiment 
  the 
  temperature 
  range 
  was 
  extended 
  to 
  — 
  72° 
  C. 
  

   and 
  as 
  the 
  open 
  circuit 
  voltage 
  of 
  the 
  cells 
  was 
  not 
  materially 
  changed 
  

   by 
  cooling 
  them 
  to 
  this 
  temperature, 
  the 
  work 
  was 
  extended 
  to 
  

   — 
  170° 
  C. 
  because 
  of 
  the 
  theoretical 
  interest 
  in 
  the 
  application 
  of 
  the 
  

   Gibbs-Helmholtz 
  and 
  Nernst 
  equations 
  to 
  these 
  cells. 
  

  

  Two 
  methods 
  of 
  cooling 
  the 
  cells 
  were 
  employed. 
  For 
  the 
  range 
  

   +25° 
  to 
  —72° 
  C, 
  the 
  cells 
  were 
  submerged 
  in 
  a 
  gasoline 
  bath 
  to 
  which 
  

   small 
  amounts 
  of 
  carbon 
  dioxide 
  snow 
  were 
  added 
  gradually 
  until 
  the 
  

  

  ^ 
  Published 
  by 
  permission 
  of 
  the 
  Director 
  of 
  the 
  Bureau 
  of 
  Standards. 
  Received 
  Jan- 
  

   uary 
  6, 
  1922. 
  

  

  