﻿CONTENTS 
  

  

  Originai, 
  Papers 
  

  

  Page 
  

  

  Minerology. 
  — 
  Tschermigite 
  (Ammonium 
  Alum) 
  from 
  Wyoming. 
  E. 
  ThEODorb 
  

   Erickson 
  49 
  

  

  Botany. 
  — 
  On 
  the 
  species 
  of 
  Dalbergia 
  of 
  Mexico 
  and 
  Central 
  America. 
  H. 
  Pitti^r. 
  ... 
  54 
  

  

  Electricity. 
  — 
  Electromotive 
  force 
  of 
  cells 
  at 
  low 
  temperatures. 
  G. 
  W. 
  Vinai. 
  and 
  

   P. 
  W. 
  Altrup 
  64 
  

  

  Abstracts 
  

   Geology 
  71 
  

  

  