﻿270 
  A. 
  M. 
  Mayer— 
  On 
  the 
  Flotation 
  of 
  

  

  iron 
  wire, 
  l 
  mm 
  thick, 
  was 
  attached 
  to 
  the 
  slide 
  and 
  micrometer 
  

   screw 
  already 
  described 
  in 
  connection 
  with 
  the 
  experiment 
  on 
  

   the 
  disks. 
  The 
  following 
  depths 
  were 
  measured. 
  They 
  are 
  

   the 
  depths 
  given 
  by 
  the 
  micrometer 
  screw 
  readings 
  plus 
  the 
  

   computed 
  elevation 
  of 
  the 
  water 
  in 
  the 
  vessel 
  caused 
  by 
  the 
  

   depression 
  of 
  the 
  ring 
  in 
  the 
  water 
  -surface. 
  

  

  1) 
  

  

  •507 
  cm 
  

  

  2) 
  

  

  •502 
  

  

  3) 
  

  

  •503 
  

  

  4) 
  

  

  •503 
  

  

  5) 
  

  

  •500 
  

  

  6) 
  

  

  503 
  

  

  ■503 
  = 
  mean 
  

  

  Experiments 
  on 
  the 
  rings. 
  

  

  Let 
  circ 
  / 
  = 
  the 
  circumference 
  of 
  the 
  axis 
  of 
  a 
  ring; 
  then 
  

  

  W 
  

  

  _ 
  — 
  =w— 
  the 
  breaking 
  weight 
  per 
  centimeter 
  of 
  circumfer- 
  

   circ' 
  e 
  s 
  I 
  

  

  ence 
  of 
  the 
  ring. 
  Let 
  p 
  = 
  the 
  upward 
  hydrostatic 
  pressure 
  on 
  

  

  one 
  centimeter 
  of 
  the 
  ring. 
  For^> 
  we 
  take 
  •00784, 
  supposing 
  

  

  that 
  the 
  two 
  opposite 
  depressed 
  surfaces 
  of 
  the 
  water 
  meet 
  at 
  

  

  the 
  instant 
  the 
  ring 
  sinks. 
  Let 
  A 
  = 
  the 
  surface 
  tension 
  of 
  water 
  

  

  in 
  grams 
  per 
  centimeter. 
  

  

  Experiments 
  on 
  the 
  ring 
  of 
  Iron. 
  

  

  Diameter 
  of 
  axis 
  of 
  ring 
  5*455 
  

  

  Circumference 
  " 
  " 
  ._ 
  _ 
  17*137 
  

  

  Temp, 
  of 
  water 
  16°. 
  

   W 
  

  

  2-866 
  min. 
  

   •891 
  

  

  •871 
  

   •886 
  

   •884 
  

   •894 
  max. 
  

  

  2*882 
  = 
  mean 
  

   W 
  2*882 
  

  

  circ 
  17*137 
  

  

  16817=^ 
  

  

  A 
  w—p 
  , 
  -16817 
  — 
  "00784 
  

   A= 
  --4-cos 
  2|=, 
  r-*999048 
  = 
  *08023 
  

  

  