﻿ACADEMY 
  OF 
  SCIENCES. 
  357 
  

  

  them 
  Ling 
  or 
  Links. 
  Another 
  species, 
  Trapa 
  natans, 
  grows 
  in 
  

   middle 
  and 
  southern 
  Europe, 
  middle 
  Asia, 
  and 
  northern 
  and 
  central 
  

   Africa, 
  and 
  the 
  fruit 
  or 
  nut 
  has 
  four 
  spines. 
  Trapa 
  hispinosa 
  is 
  

   found 
  in 
  Asia 
  and 
  parts 
  of 
  Africa, 
  and 
  it 
  is 
  said 
  also 
  to 
  be 
  culti- 
  

   vated 
  in 
  Japan. 
  In 
  some 
  of 
  these 
  countries 
  this 
  latter 
  species 
  is 
  

   an 
  important 
  staple 
  in 
  the 
  way 
  of 
  food 
  to 
  the 
  population. 
  The 
  

   nuts 
  are 
  held 
  in 
  high 
  estimation 
  by 
  the 
  Hindoos, 
  and 
  are 
  sold 
  in 
  all 
  

   the 
  shops 
  in 
  India. 
  Quite 
  likely 
  some 
  one 
  of 
  these 
  species 
  might 
  

   thrive 
  well 
  in 
  this 
  country, 
  and 
  it 
  would 
  be 
  well 
  for 
  some 
  enterpris- 
  

   ing 
  Californian 
  to 
  experiment 
  with 
  the 
  Chinese 
  species, 
  the 
  seeds 
  

   of 
  which 
  are 
  easily 
  obtainable 
  in 
  this 
  city. 
  

  

  Donations 
  to 
  the 
  Library 
  : 
  In 
  addition 
  to 
  the 
  usual 
  periodicals 
  and 
  exchanges 
  

   the 
  Library 
  received 
  : 
  Annual 
  Reports 
  of 
  the 
  Chief 
  Signal 
  Officer 
  to 
  the 
  Sec- 
  

   retary 
  of 
  War, 
  for 
  years 
  1872 
  and 
  1873. 
  Weekly 
  Weather 
  Chronicle. 
  Daily 
  

   Bulletin, 
  synopses, 
  probabilities, 
  and 
  facts 
  of 
  the 
  month 
  of 
  June, 
  1874. 
  Daily 
  

   Bulletin 
  of 
  weather 
  reports, 
  Signal 
  Service 
  U. 
  S. 
  A., 
  taken 
  at 
  Washington, 
  

   with 
  the 
  synopses, 
  probabilities, 
  and 
  facts 
  for 
  September, 
  1872 
  ; 
  all 
  four 
  of 
  

   these 
  were 
  presented 
  by 
  H. 
  W. 
  Howgate, 
  U. 
  S. 
  A. 
  Dr. 
  M. 
  Linderman 
  Bre- 
  

   nan 
  presented 
  the 
  second 
  part 
  of 
  the 
  Report 
  of 
  the 
  last 
  German 
  Polar 
  Expedi- 
  

   tion. 
  Albert 
  J. 
  Mayer, 
  Chief 
  Signal 
  Officer, 
  U. 
  S. 
  A., 
  presented 
  circular 
  upon 
  

   the 
  " 
  Practical 
  Use 
  of 
  Meteorological 
  Reports 
  and 
  Weather 
  Maps." 
  Ross' 
  

   Voyage 
  of 
  Discovery 
  to 
  Baffin's 
  Bay. 
  This 
  book 
  is 
  interesting, 
  as 
  having 
  

   been 
  found 
  with 
  others, 
  on 
  the 
  12th 
  of 
  April, 
  1873, 
  on 
  Ocean 
  Island, 
  North 
  

   Pacific, 
  remaining 
  from 
  the 
  wreck 
  of 
  the 
  U. 
  S. 
  S. 
  Saginaw, 
  by 
  J. 
  C. 
  Werner, 
  

   presented 
  by 
  W. 
  G. 
  W. 
  Harford. 
  

  

  On 
  the 
  Structure 
  of 
  the 
  Sonorous 
  Sand 
  from 
  Kauai. 
  

  

  BY 
  JAMES 
  BLAKE. 
  

  

  In 
  order 
  to 
  ascertain, 
  if 
  possible, 
  the 
  cause 
  of 
  the 
  sound 
  that 
  is 
  produced 
  by 
  

   the 
  sand 
  from 
  Kauai, 
  presented 
  to 
  the 
  Academy 
  at 
  a 
  former 
  meeting, 
  I 
  investi- 
  

   gated 
  its 
  structure 
  under 
  the 
  microscope, 
  and 
  I 
  think 
  the 
  facts 
  I 
  have 
  ascer- 
  

   tained 
  fully 
  explain 
  the 
  manner 
  in 
  which 
  the 
  sound 
  is 
  produced. 
  As 
  the 
  grains 
  of 
  

   sand, 
  although 
  small, 
  are 
  quite 
  opaque, 
  it 
  was 
  necessai'y 
  to 
  prepare 
  them 
  so 
  

   that 
  they 
  should 
  be 
  sufficiently 
  transparent 
  to 
  render 
  their 
  structure 
  visible. 
  

   This 
  was 
  effected 
  by 
  fastening 
  them 
  to 
  a 
  glass 
  slide 
  and 
  grinding 
  them 
  down 
  

   until 
  one 
  flat 
  surface 
  was 
  obtained. 
  This 
  surface 
  was 
  then 
  attached 
  to 
  another 
  

   slide, 
  and 
  the 
  original 
  slide 
  being 
  removed, 
  the 
  sand 
  was 
  again 
  ground 
  down 
  

   until 
  sufficiently 
  transparent. 
  The 
  grains 
  were 
  found 
  to 
  be 
  chiefly 
  composed 
  of 
  

   small 
  portions 
  of 
  coral 
  and 
  apparently 
  calcareous 
  sponges, 
  and 
  presented 
  under 
  

   the 
  microscope 
  a 
  most 
  interesting 
  object. 
  They 
  were 
  all 
  more 
  or 
  less 
  per- 
  

   forated 
  with 
  small 
  holes, 
  in 
  some 
  instances 
  forming 
  tubes, 
  but 
  mostly 
  terminat- 
  

   ing 
  in 
  blind 
  cavities, 
  which 
  were 
  frequently 
  enlarged 
  in 
  the 
  interior 
  of 
  the 
  

  

  