CITY TALK : Follow Dieter out of Lonrho

SO, farewell then, Dieter Bock. The one-time chief executive of Lonrho, more recently its non-executive deputy chairman, has finally quit the group from which he ousted its original architect, Tiny Rowland. But as shareholders look back on his brief reign, what can they claim he has done for them?

True, he set about breaking up Lonrho. But a deal finally to separate the mining arm from the African trading business looks as far off as it ever did and is now bogged down at the European Commission, which is shortly expected to announce onerous restrictions on Anglo American's stake.

Nor is there any news on the sale of the remaining Princess hotels, where talks with Saudi Prince al-Waleed bin Talal have also stalled. Meanwhile, several strategies chosen by Mr Bock - such as splitting the group up, floating off the hotels business, and selling its platinum mining business to South Africa's Gencor - have all had to be abandoned.

The German property man himself, though, has done rather well. The sale of his stake in Lonrho at 180p has reputedly netted him upwards of pounds 100m, plus a generous salary for his time. If Mr Bock claimed he would maximise returns for shareholders, he certainly more than managed that for one of them. The shares, at 147.5p, are up from under pounds 1 when he joined four years ago, but there seems little incentive to hold them now.

Over the next few weeks, you could be hearing more of another biotechnology start-up, Chemunex, which has developed a technology to test for bugs and impurities. The company is in the midst of a placing on Easdaq - the Europe-wide stock market for nascent companies.

Aha, say those of you who follow the sector, sounds similar to what Celsis does. Well, yes and no. Celsis, for a start, is far more advanced and prefers not to be classed as a pure biotech stock - the know-how it uses is already on sale, and it is well on course to reach break-even. Chemunex's technology, by contrast, while arguably more sophisticated, is at an earlier stage of development. And its greater sensitivity means that it will find applications where extremely accurate tests are needed, such as drug companies. Celsis has a much wider market so scare stories that it may be unseated are wide of the mark.

Directors' share sales were seen last week at Greenalls, the brewing to hotels group where Andrew Thomas, the chairman and chief executive, sold 30,276 at 560.5p each to cut his holding to 90,000. At another brewer, Morlands, of Old Speckled Hen fame, director of retail operations Peter Furness-Smith sold 2,550 shares at 590p, or almost half of his holding. He now has 7,179 shares.

Greenalls, after a spectacular rise from 400p two years ago to a high of 633p in May last year - and a brief stint in the FT-SE 100, has been stuck in a rut since then, trading between 550p and 580p. Perhaps Mr Thomas suspects the best is past. And Mr Furness-Smith too.

Tadpole, the computer concern that specialises in whizzy laptops, had another rough time this week, with its shares falling 11 per cent to 26p.

However, while Tadpole continues to go through a torrid time, a UK winner in the computer stakes, Psion, surges ahead. It closed the week at 432.5p, up from 421.5p on Monday. Not even a negative newspaper report that software giant Microsoft wants to muscle in on the hand-held market - where Psion is a world leader - could upset the shares. Microsoft will sell its CE hand-held computers this summer. They are expected to retail at pounds 550, compared with only pounds 400 for a similar machine from Psion.

More positive news came on Tuesday when the World Trade Organisation announced it was close to agreeing tariffs on computer equipment, which will benefit Psion. The company reports full-year results tomorrow, when chairman and founder David Potter is due to present the figures after returning from an emergency heart bypass operation before Christmas.

Heal's, the upmarket furniture stores group, is in the midst of putting the finishing touches to its flotation plans. The group hopes to come to the market on 18 March, with first dealings expected on 24 March. It launched its pathfinder prospectus last week, which showed a strong improvement in sales, profits and sales densities. Management seems to be doing a good job and Christmas sales surpassed expectations, so there seems every likelihood the shares will follow in the footsteps of Harvey Nichols.

Expect another success.