﻿72 
  

  

  Anniversary 
  Meeting. 
  

  

  [Nov. 
  30, 
  

  

  Reports 
  to 
  the 
  British 
  Association 
  and 
  the 
  contributions 
  to 
  the 
  Philo- 
  

   sophical 
  Magazine 
  (1853, 
  1856, 
  1857), 
  in 
  which 
  he 
  grappled 
  with 
  the 
  

   subject 
  of 
  slaty 
  cleavage, 
  and 
  helped 
  to 
  establish 
  the 
  explanation 
  that 
  

   cleavage 
  was 
  the 
  result 
  of 
  greater 
  relative 
  condensation 
  of 
  the 
  material 
  

   in 
  a 
  direction 
  perpendicular 
  to 
  the 
  cleavage, 
  due 
  in 
  the 
  case 
  of 
  rocks 
  to 
  

   mechanical 
  compression 
  in 
  that 
  direction 
  — 
  an 
  idea 
  that 
  met 
  with 
  imme- 
  

   diate 
  illustration 
  from 
  other 
  experimentalists. 
  

  

  His 
  memoirs 
  on 
  the 
  temperatures 
  and 
  pressures 
  at 
  which 
  certain 
  rocks 
  

   and 
  minerals 
  were 
  formed 
  (in 
  the 
  Geological 
  Society's 
  Journal, 
  1858), 
  

   founded 
  on 
  the 
  relative 
  volume 
  of 
  the 
  liquid 
  and 
  vacuous 
  portions 
  of 
  

   microscopic 
  hollows, 
  or, 
  again, 
  on 
  the 
  character 
  of 
  microscopic 
  substances 
  

   mingled 
  with 
  the 
  mineral 
  matter 
  he 
  investigated, 
  convinced 
  the 
  geologist 
  

   that 
  he 
  had 
  to 
  take 
  into 
  account 
  the 
  action 
  of 
  water 
  under 
  high 
  pressures 
  

   and 
  at 
  high 
  temperatures 
  in 
  explaining 
  the 
  formation 
  of 
  granitoid 
  rocks. 
  

  

  And 
  the 
  refinement 
  of 
  the 
  methods 
  that 
  Mr. 
  Sorby 
  employed 
  for 
  making 
  

   his 
  rock-sections 
  at 
  Sheffield 
  has 
  made 
  those 
  methods 
  the 
  models 
  sought 
  

   after 
  by 
  the 
  now 
  large 
  school 
  of 
  Continental 
  and 
  English 
  microscopic 
  

   petrologists. 
  

  

  His 
  applications 
  of 
  spectroscopic 
  methods 
  to 
  the 
  microscope 
  fall 
  more 
  

   strictly 
  within 
  the 
  limit 
  of 
  ten 
  years, 
  as 
  they 
  have 
  been 
  worked 
  out 
  since 
  

   1867, 
  when 
  Mr. 
  Sorby 
  first 
  described 
  his 
  adaptation 
  of 
  the 
  spectroscope 
  

   to 
  the 
  microscope, 
  as 
  carried 
  out 
  by 
  Mr. 
  Browning. 
  

  

  The 
  observations 
  he 
  has 
  made 
  with 
  this 
  instrument, 
  and 
  generally 
  by 
  

   combining 
  optical 
  examination 
  with 
  the 
  use 
  of 
  chemical 
  reagents, 
  have 
  ex- 
  

   tended 
  over 
  a 
  very 
  wide 
  range 
  — 
  such 
  as 
  the 
  recognition 
  of 
  blood-stains, 
  of 
  

   adulteration 
  in 
  wine, 
  the 
  means 
  of 
  discriminating 
  among 
  the 
  compounds 
  of 
  

   certain 
  of 
  the 
  metals, 
  chiefly 
  of 
  zirconium, 
  titanium, 
  and 
  uranium, 
  by 
  the 
  

   aid 
  of 
  blowpipe-beads 
  — 
  and 
  finally 
  to 
  the 
  elucidation, 
  to 
  a 
  considerable 
  

   extent, 
  of 
  the 
  causes 
  of 
  the 
  complexity 
  in 
  the 
  tints 
  exhibited 
  by 
  plants 
  in 
  

   the 
  different 
  stages 
  of 
  development 
  of 
  their 
  annual 
  foliage 
  and 
  flowers. 
  

  

  These 
  are 
  only 
  some 
  of 
  the 
  more 
  important 
  of 
  Mr. 
  Sorby's 
  contributions 
  

   to 
  science 
  ; 
  and 
  they 
  are 
  characterized 
  by 
  an 
  untiring 
  application 
  of 
  the 
  

   methods 
  of 
  experimental 
  research 
  to 
  a 
  great 
  variety 
  of 
  subjects 
  suggested 
  

   by 
  a 
  very 
  ingenious 
  and 
  active 
  mind. 
  

  

  The 
  Medal 
  was 
  received 
  by 
  Mr. 
  Sorby. 
  

  

  A 
  Eoyal 
  Medal 
  has 
  been 
  awarded 
  to 
  Prof. 
  William 
  Crawford 
  William- 
  

   son, 
  F.R.S., 
  " 
  for 
  his 
  Contributions 
  to 
  "Zoology 
  and 
  Palaeontology, 
  and 
  

   especially 
  for 
  his 
  Investigation 
  into 
  the 
  Structure 
  of 
  the 
  Fossil 
  Plants 
  of 
  

   the 
  Coal-Measures." 
  

  

  Professor 
  Williamson's 
  contributions 
  to 
  Biological 
  Science 
  were 
  com- 
  

   menced 
  forty 
  years 
  ago, 
  and 
  embrace 
  investigations 
  into 
  the 
  structure 
  of 
  

   the 
  Poraminifera, 
  the 
  Rotifera, 
  the 
  scales 
  and 
  bones 
  of 
  Fishes, 
  and 
  the 
  

   fossil 
  plants 
  of 
  the 
  Carboniferous 
  and 
  Oolitic 
  periods. 
  These 
  comprise 
  

   works 
  of 
  great 
  merit 
  and 
  value, 
  not 
  only 
  on 
  account 
  of 
  their 
  accuracy 
  

  

  