Raymond Baxter

Anthony Hayward's excellent obituary [18 September] brought back many memories of Raymond Baxter's contributions to Tomorrow's World, writes Professor Mike Bader. His explanations were eloquent, accurate with never a wasted word; the finer detail being pointed out with, what became his trademark, his silver propelling pencil. As for the "ball wheelbarrow", it most definitely saw the light of day. I still have one in regular use - it has seen better days but has never been bettered! I would buy another if it were still in production.

James Dyson, of course, developed just such a Ballbarrow in 1974, writes Ron Livingstone, and it won the Building Design Innovation Award in 1978. The idea was developed further in the Trolleyball in 1978 - a boat launcher using the same principle of replacing wheels with balls.

Raymond Baxter was a frequent contributor to geography programmes for BBC Schools Radio in the 1960s and 1970s, writes Geoffrey Sherlock. His enthusiasm for technical topics carried sometimes difficult ideas through to audiences of a wide range of ages and abilities. We planned, broadcast and enjoyed such topics as the pumped hydroelectricity scheme at Dinorwig in North Wales, the discovery of gas in the North Sea (this programme went out live as we waited for the final discovery of gas at one well) and tourism in the Isle of Man and its links to the TT races.

He was a joy to work with and travelling to record interviews was memorable as he drove a Mini with an Austin Healey 3000 engine in it. We tended to leave most other traffic in our wake.