[quote=doug adams]" Ideally I need to run a single hose extension for about 30 feet from the tap and then have an arrangement which divides into four different branches. Is there some kind of product which would achieve this and
take four different timers?[/color]

Gardena make a 5 or 6-way splitter. Connect one hose via a timer to the gizmo, and it'll feed one outlet. Every time the timer sitches off and then on again, the gizmo automatically switches to the next output. All you need to do is to get your timer to switch on/off 4 times, and each area of your garden will get watered with full pressure.