Lot 100 : General - Imperial AirwaysGeneral - Imperial Airways : CAPE TOWN-LONDON 1ST REGULAR RETURN SERVICE Cape Town-Salisbury, 4d Air & 1d (SG40 & 31) of South Africa, tied with Cape Town 27 Jan 32 cds cancel. On Robertson illust cover. Additional Air Mail label tied by the cancel. Addressed to Salisbury. On the reverse Salisbury 28 Jan 32 receiving.