The sender ostensibly mailed this envelope to his wife in India. Earlier in the 1930’s the Belgian postal authorities had frowned on self addressed post-restante letters, as they were always out of pocket from the return journey. This assertion is well proved here, as shown below, but for the Indian post office! Hence, using his wife as addressee gave some legitimacy to his action.

1938 Belgium letter to Gwalior

Letter to Gwalior, recto – note buff sticker protrudes above and below white one

The letter was mailed from Brussels GPO on 3 March 1938, and directed to go by Imperial Airways. From Brussels it went to London. For a long time I could not make any sense of the 560 Fr paid for the postage (60c on the back). It was not until I learnt that on 28 February 1938 the unit Empire rate to India had reduced from 6d to 1½d that some light dawned. Here, maybe, was the real reason for the letter’s despatch; an early example of the new rate.

The letter arrived in Gwalior 11 March (cds backstamp), and then when unclaimed, it was returned to Bombay (Bombay DLO 18 Mar 38 backstamp). The next day it was returned (DLO Bombay 19 Mar 38 backstamp) to Gwalior (buff stick on note – invisible – with DLO Bombay 19 Apr 38 and m/s Gwalior, for consignment through DLO). The white stick on note (front) bears DLO Gwalior 21 Mar 38 and m/s to DLO Bombay; also see the DLO Gwalior 21 Apr 38 backstamp.

The next mark was DLO Bombay 23 Apr 38 (received). Then there is a Bombay DLO used to cancel the 10c rear stamp (DLO Bombay 25 Apr 38), and finally for India Bombay GPO Reg cds cancel dated 25 Apr 38.

The final cancellation was Brussels 20 May 38 (cancelling both 50 & 10c stamps) on receipt back in Brussels, having been returned by boat and train.

Letter to Gwalior, verso – flap is at bottom, ie inverted

Now let us consider the postage paid. The second clue was the envelope flap being tucked in. The central top (bottom as illustrated) DLO Bombay 18 Apr 38 struck both flap and body and proves this. Most likely nothing was included. Thus the basic postage rate was for printed rate letter at 35c. Registration was 175 Fr (Brussels 1 registration sticker is under the stick on notes). These add up to 2.10 Fr, leaving 3.50 Fr for the airmail.

Officially, the general airmail rate, as published by the Belgian postal authorities, did not reduce from 4.50 Fr to 3.50 Fr (per 5 gms) to India until 1 May 1938. Hence our savvy collector got his reduced rate letter through the system some two months early. But his new rate was 77%, not the 25% for Commonwealth members. Still us and them?

The 5 Fr red-brown stamp used, showing a plane over Brussels, was issued on 30 April 1930 specifically for airmail letters. (It was demonetised 1 April 1948). The brown-violet version was issued 3 December 1930 specifically for the Vanderlinden & Fabry first airmail delivery to the Belgian Congo, which left Brussels 7 December 1930 for Leopoldville.

References
Catalogue de Timbres-Poste Belgique, 2002, Belgium
La Poste Aerienne en Belgique, ses debuts, ses tariffs, E & M Deneumostier, 1989
Tarifs Postaux Internationaux 1892-1988, vol 3, E & M Deneumostier, 1990