OVERVIEW

ABSTRACT: The third Britisher who, in addition to Alastair Denniston and Dillwyn Knox, met the Poles near Pyry in 1939 to to receive a copy of the Enigma machine has been wrongly identified as Stewart Menzies, head of the British foreign intelligence service. In fact he was Humphrey Sandwith, head of the Admiralty's interception and direction-finding service.

KEYWORDS: Menzies, Sandwich, Sandwith, Pyry, Enigma.

On 24 July 1939 representatives of the French Service de Renseignements and of the British Secret Intelligence Service met with some of their opposite numbers of the Polish Intelligence Service in the forest near Pyry, a town some 20 kilometers southeast of Warsaw. Six weeks later such a meeting would have been impossible because Germany had invaded, and was rapidly overrunning, Poland. But as it was, in the very nick of time, this most secret conference resulted in the presentation by the Poles to the French and the British of all the fruits of their successful attack, codenamed Wicher, on the German Enigma cipher system, and a firm agreement for future co-operation between the cryptanalysis teams of the three countries. This was to have a profound, some would say a decisive, influence on the outcome of World War II.

All this is now common knowledge, although there still seems to be some dispute amongst the experts (of whom I am certainly not one) about the exact value of the Polish contribution. Professor F. H. Hinsley has stated that it merely helped the...