1. Introduction

   • J. M. Bačkovský

   EditorialNotes Pages: 1 - 2

2. A new method for calculating the energy levels of electrons in solids

   • Zdeněk Matyáš

   OriginalPaper Pages: 3 - 9

3. The construction of a linear analyser in Czechoslovakia

   • Antonín Svoboda

   OriginalPaper Pages: 10 - 18

4. On Sahánek's relation for the generation of short electromagnetic waves in electron tubes

   • Josef Habanec

   OriginalPaper Pages: 19 - 23

5. Report on gravimetric measurements carried out at points of the basic gravimetric net-work during 1948 and 1949 on the territory of Czechoslovakia

   • Jan Pícha

   OriginalPaper Pages: 24 - 26

6. New trends in microscopy

   • Jarmila Dolejší
   • Karel Slonek

   OriginalPaper Pages: 27 - 42

7. Death of academician S. I. Vavilov

   • Zdeněk Pírko

   Items Pages: 43 - 45

8. First International Polarographic Congress in Prague

   • J. V. A. Novák

   Items Pages: 45 - 47

9. Reviews

   • V. Kunzl
   • Z. Pírko

   BookReview Pages: 47 - 48