﻿Chemistry 
  and 
  Physics. 
  383 
  

  

  constitution 
  is 
  confined 
  in 
  this 
  large 
  book 
  to 
  a 
  chapter 
  of 
  only 
  42 
  

   pages. 
  

  

  The 
  book 
  is 
  well 
  arranged, 
  with 
  an 
  interesting 
  introduction 
  

   and 
  chapters 
  which 
  classify 
  the 
  natural 
  dyestuffs 
  according 
  to 
  

   the 
  chemical 
  groups 
  to 
  which 
  they 
  belong. 
  There 
  are 
  copious 
  

   references 
  to 
  the 
  chemical 
  literature, 
  and 
  it 
  should 
  be 
  extremely 
  

   useful 
  to 
  all 
  chemists 
  who 
  are 
  interested 
  in 
  the 
  constitution 
  of 
  

   dyestuffs. 
  h. 
  l. 
  w. 
  

  

  4. 
  Chemistry 
  in 
  Old 
  Philadelphia; 
  by 
  Edgar 
  F. 
  Smith. 
  8vo, 
  

   pp. 
  106. 
  Philadelphia, 
  1919 
  (Printed 
  by 
  the 
  J. 
  B. 
  Lippincott 
  

   Company). 
  — 
  Within 
  the 
  past 
  four 
  or 
  five 
  years 
  we 
  have 
  been 
  

   indebted 
  to 
  Dr. 
  Smith 
  for 
  two 
  sumptuous 
  volumes, 
  important 
  

   contributions 
  to 
  the 
  history 
  of 
  American 
  Chemistry, 
  entitled 
  

   "Chemistry 
  in 
  America" 
  and 
  "The 
  Life 
  of 
  Robert 
  Hare." 
  We 
  

   now 
  welcome 
  this 
  additional 
  contribution, 
  material 
  for 
  which 
  has 
  

   been 
  found, 
  as 
  the 
  author 
  says, 
  "in 
  ancient 
  volumes, 
  musty 
  

   documents 
  and 
  seared 
  and 
  forgotten 
  letters." 
  

  

  The 
  earliest 
  chemist 
  mentioned 
  is 
  Dr. 
  deNormandie, 
  of 
  whom 
  

   nothing 
  is 
  known 
  except 
  that 
  he 
  published 
  an 
  account 
  of 
  the 
  

   examination 
  of 
  a 
  spring 
  water, 
  and 
  actually 
  used 
  a 
  balance 
  in 
  

   this 
  connection 
  as 
  early 
  as 
  1768. 
  The 
  following 
  year, 
  1769. 
  was 
  

   the 
  date 
  of 
  the 
  appointment 
  of 
  the 
  celebrated 
  Dr. 
  Benjamin 
  Rush 
  

   at 
  the 
  University 
  of 
  Pennsylvania, 
  the 
  first 
  professor 
  of 
  Chem- 
  

   istry 
  in 
  America 
  and 
  a 
  signer 
  of 
  the 
  Declaration 
  of 
  Independence. 
  

   Very 
  interesting 
  information 
  is 
  given 
  in 
  regard 
  to 
  Woodhouse, 
  

   under 
  whom 
  Benjamin 
  Silliman 
  studied 
  chemistry, 
  concerning 
  

   Seybert, 
  who 
  described 
  many 
  mineral 
  analyses 
  in 
  the 
  early 
  

   volumes 
  of 
  this 
  Journal, 
  while 
  additional 
  facts 
  are 
  given 
  concern- 
  

   ing 
  the 
  famous 
  Joseph 
  Priestley's 
  life 
  in 
  America. 
  Only 
  a 
  sum- 
  

   mary 
  of 
  the 
  work 
  of 
  Robert 
  Hare 
  is 
  given, 
  since 
  this 
  has 
  been 
  

   treated 
  elaborately 
  in 
  the 
  author's 
  "Life." 
  Incidents 
  in 
  con- 
  

   nection 
  with 
  many 
  other 
  early 
  Philadelphia 
  chemists 
  are 
  given, 
  

   and 
  the 
  book 
  is 
  an 
  exceedingly 
  interesting 
  and 
  readable 
  one. 
  

  

  h. 
  l. 
  w. 
  

  

  5. 
  Forms 
  Assumed 
  by 
  Drops 
  and 
  Vortices. 
  — 
  In 
  the 
  usual 
  

   methods 
  of 
  producing 
  vortices 
  the 
  various 
  stages 
  of 
  the 
  phenom- 
  

   enon 
  succeed 
  one 
  another 
  with 
  great 
  rapidity, 
  so 
  that 
  either 
  

   unusually 
  acute 
  observation, 
  or 
  instantaneous 
  illumination 
  and 
  

   photography, 
  is 
  required 
  to 
  isolate 
  any 
  particular 
  one. 
  A 
  verj^ 
  

   ingenious 
  method 
  for 
  producing 
  permanent 
  three-dimensional 
  

   records 
  of 
  vortical 
  forms 
  has 
  been 
  devised 
  and 
  thoroughly 
  tested 
  

   by 
  Emil 
  Hatschek. 
  The 
  fundamental 
  idea 
  was 
  to 
  produce 
  

   drops 
  or 
  vortices 
  of 
  a 
  suitably 
  colored 
  gelatin 
  sol 
  in 
  one 
  of 
  the 
  

   numerous 
  solutions 
  which 
  promote 
  the 
  setting 
  of 
  gelatin 
  sols 
  or 
  

   cause 
  hardening 
  of 
  gelatin 
  gels. 
  Apart 
  from 
  the 
  possibility 
  of 
  

   arresting 
  the 
  vortex 
  at 
  any 
  given 
  stage 
  by 
  the 
  proper 
  choice 
  of 
  

   solution 
  and 
  concentrations, 
  this 
  procedure 
  gave 
  results 
  which 
  

  

  