15 AUGUST 1958, Page 18

SIR,—Information on most of the subjects on which Leslie Adrian

writes I have to accept in faith. It is a blow to that faith to find that on the one subject know a little about the information is full of errors.

The transistor is a notable exception to the rule that dates of invention are ill-defined; it was invented in 1948 at the Bell Telephone Laboratories in USA by Bardeen and Brattain. I am therefore surprised to be told that it was invented before the war. We are not told which war, so of course it might be the recent one in Iraq, but most people would assume that the 1939-45 war was meant.

Then it is not true that only in the last two years have they been developed in the field of deaf aids; this happened within a few years of the first invention. And as regardS the relative prices of valves and tran- sistors, Leslie Adrian has got them the wrong, way round. I would recommend him in future to seek more authoritative sources than the odd `man in the trade.'

Elstree Hill Laboratory, Bromley, Kent [Leslie Adrian writes : ' "The odd man in the trade" has gone on holidays : he will get a jobation on his return. But I must plead not guilty to the trans- position of the prices of valves and transistors, which occurred after the copy had left my hands.'—Editor, Spectator.]