One of many trade adverts issued by London Transport's Commercial Advertising Department; selling advertising space on the Board's vehicles and premises was an important ancilliary revenue stream and LT put the same level of thought and quality into the graphic design of such publicity as they did their public posters. This December 1934 is selling transparent window adverts in the then doomed tramway fleet - the plan being to replace them all by trolleybuses by c.1940. The intervention of war saw the trams, in South London, survive until 1952.
The advert panels shown are for the well known Hayward's Military Pickle and consisted of transfers, either varnish or water fixed, than went on windows. The advert itself is not set in LT's own Johnston typeface but in Koch's design of Kable/Cable issued by Klingspor. Johnston does appear on the London Transport Tramway's version of the roundel. Post-formation in 1933 LT worked with Edward Johnston to produce a series of roundels to show the operating 'mode' that, with the words of London and Transport in the white semi-circles are slightly, visually, cluttered.