Page proofs of the issue which lack pages 50, 64 and 65; there are two copies of pages 51-63. An additional typescript sheet of references is inserted before page 15, and a printed statement inserted at the end, intended for the back cover of the magazine. The proofs have been corrected in various hands throughout. Corrections and minor editing in blue are by Michael Schmidt; and David Martin has amended his own introduction to the issue in black. There are also corrections throughout in pencil and black pen. The two sets of pages 51-63 have been marked up with different corrections. The set has been marked on the reverse of the final sheet as 'final proofs'.