P ostcodes Sir: In 1969, the PO stated: `The figure of
£24 million is the amount we expect to invest in automatic letter coding equipment over the next ten years. When the system is in full swing, the annual return is expected to exceed 20 per cent.' However, £44 million for investment in mechanisation was quoted during the parliamentary debate on the PO (Borrowing) Bill in November 1972. A year later, a national newspaper reported the existence of an £83 million postal codes scheme. Just what is the cost of this particular superstructure now; what is yet to be spent on the .sophisticated system; and what has been haPpening to 'the annual return'? Alpha-numeric symbolism (as distinct from postal guide-numbers) may be indispensable to alpha-numeric equipment, but not to a national postal service as such. Peter Ratazzi 90 Nevill Avenue, Hove, Sussex