﻿THE 
  

   LONDON, 
  EDINBURGH, 
  and 
  DUBLIN 
  

  

  PHILOSOPHICAL 
  MAGAZINE 
  

  

  AND 
  

  

  JOURNAL 
  OF 
  SCIENCE. 
  

  

  CONDUCTED 
  BY 
  

  

  LORD 
  KELVIN, 
  GkC.V.O. 
  D.C.L. 
  LL.D. 
  F.R.S. 
  (fee. 
  

   JOHN 
  JOLY, 
  M.A. 
  D.Sc. 
  F.R.S. 
  F.G.S. 
  

  

  AND 
  

  

  WILLIAM 
  FRANCIS, 
  Ph.D. 
  F.L.S. 
  F.R.A.S. 
  F.O.S. 
  

  

  " 
  Nee 
  aranearum 
  sane 
  textus 
  ideo 
  melior 
  quia 
  ex 
  se 
  fila 
  gignunt, 
  nee 
  noster 
  

   vilior 
  quia 
  ex 
  alienis 
  libamus 
  ut 
  apes." 
  Just. 
  Lips. 
  Polit. 
  lib. 
  i. 
  cap. 
  1 
  . 
  Not. 
  

  

  VOL. 
  III.— 
  SIXTH 
  SERIES. 
  

   JANUARY— 
  JUNE 
  l'£02. 
  

  

  LONDON: 
  

   X 
  AND 
  FRANCIS, 
  RED 
  LION 
  COURT, 
  FLEET 
  STREET. 
  

  

  SOI 
  >KIN, 
  MARSHALL, 
  HAMILTON, 
  KENT, 
  AND 
  CO., 
  LD. 
  T. 
  AND 
  T. 
  CLAKK 
  

  

  BURGH 
  ;— 
  SMITH 
  AND 
  SON, 
  GLASGOW 
  ;— 
  HODGES, 
  FIGGIS, 
  AND 
  

   , 
  DU3LINJ 
  — 
  PUTNAM, 
  NEW 
  YORK 
  ; 
  — 
  VEUVE 
  J. 
  BOYVEAU, 
  

   PARIS; 
  AND 
  AS 
  HER 
  AND 
  CO-, 
  BERLIN- 
  

  

  4 
  Q 
  1 
  i 
  O 
  

  

  