﻿THE 
  

   LONDON, 
  EDINBURGH, 
  and 
  DUBLIN 
  

  

  PHILOSOPHICAL 
  MAGAZINE 
  

  

  A 
  N 
  D 
  

  

  JOURNAL 
  OF 
  SCIENCE. 
  

  

  CONDUCTED 
  BY 
  

  

  JOHN 
  JOLY, 
  M.A. 
  D.Sc. 
  Fm£. 
  F.G.S. 
  

  

  AND 
  

  

  WILLIAM 
  FRANCIS, 
  F.L.S. 
  

  

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

   vilior 
  quia 
  ex 
  alienis 
  libamus 
  ut 
  apes." 
  Just. 
  Lips. 
  PoliL 
  lib. 
  i. 
  c&p. 
  1 
  . 
  Not 
  

  

  VOL. 
  XVL— 
  SIXTH 
  SERIES. 
  

   JULY— 
  DECEMBER 
  1908. 
  

  

  ' 
  ; 
  L'0 
  iV 
  f) 
  O 
  JS 
  ": 
  "■' 
  

   TAYLOE 
  AND 
  EEANCIS, 
  RED 
  LION 
  COUET, 
  FLEET 
  STREET, 
  

  

  SOLD 
  BY 
  SIMPKIX, 
  MARSHALL, 
  HAMILTON, 
  KENT, 
  AND 
  CO., 
  LP. 
  

  

  SMITH 
  AND 
  SOX, 
  GLASGOW: 
  — 
  HODGES, 
  FIGGIS, 
  AND 
  CO., 
  DUBLIN; 
  

  

  YEUVE 
  J. 
  BOYVEAU, 
  PARIS 
  : 
  AND 
  ASHER 
  AND 
  CO., 
  BERLIN. 
  

  

  8820'i 
  

  

  

  