1. Letters to the editor

   • Paul Weidlinger
   • Joseph Wright
   • Jacob E. Goodman

   Department Pages: 3 - 6

2. If hamilton had prevailed: quaternions in physics

   • J. Lambek

   Article Pages: 7 - 15

3. A philosopher’s mathematician: hans hahn and the vienna circle

   • Karl Sigmund

   Article Pages: 16 - 29

4. Old and new moving-knife schemes

   • Steven J. Brams
   • Alan D. Taylor
   • William S. Zwicker

   Article Pages: 30 - 35

5. Mathematical entertainments

   • David Gale

   Department Pages: 36 - 41

6. 1ooth anniversary of the jagiellonian university students’ maths society

   • Krzysztof Ciesielski

   Article Pages: 42 - 46

7. Freud on math

   • Reuben Hersh

   Article Pages: 47 - 47

8. Friedrich ii and the love of geometry

   • Heinz Götze

   Article Pages: 48 - 57

9. The mathematical tourist

   • Ian Stewart

   Department Pages: 58 - 61

10. Years ago

    • Jeremy J. Gray

    Department Pages: 62 - 63

11. Farey series and pick’s area theorem

    • Maxim Bruckheimer
    • Abraham Arcavi

    Article Pages: 64 - 67

12. Reviews

    • Jet Wimp
    • Ivor Grattan-Guinness
    • Adrian Riskin

    Department Pages: 68 - 77

13. Stamp corner

    • Robin Wilson

    Department Pages: 78 - 78