Kempston's mouse package is compatible with all Spectrums and includes the mouse itself, an interface, and a specially converted copy of Rainbird's Art Stndio designer program.

The interface uses an Atari-type joystick plug and slots straight into the expansion port at the back of the machine. It's dead-ended but monitor and disc drive drive interfaces will happily share the expansion slot with it.

The mouse is supplied in three parts: palm-sized body, rubberised track ball, and a plate which holds the ball in the body. This handy arrangement means that you can take all the moving parts out of the mouse body to clean it. The rubber textured ball will grip even the smoothest of surfaces without slipping.

There is no movement sensitivity control on the mouse but Kempston has built in a software-controlled movement scale of one to five. Setting 5 forces the mouse to travel far and wide to achieve just a little cursor movement while Setting 1 the cursor across the screen with a short flick of the mouse.

The mouse itself seemed well constructed and instructions supplied with the mouse operating software give pokes to allow the device to be used with a variety of different joystick-controlled software packages.

The Kempston version of Art Studio is the only piece of applications software supplied with the mouse package.

It's a menu-driven computer-aided design system which produces a wide range of Paint and Draw effects. Included also is a library of pre-defined shapes such as lines, triangles and circles which are created by click- selecting (using the mouse) a point of origin and definition points for circumference boundaries and points of triangles and squares. The speed at which the mouse performs these operations depends upon your agility as an operator but, even if you're a neophyte, the mouse is considerably more flexible than either keyboard or joystick.

Art Studio defaults to keyboard input unless you select mouse during the printer/peripheral installation routine which you run through every time you load the program. Your choice should be a careful one as the AMX mouse option uses a different control standard to that of Kempston and, You can't change the input device once you've got into the package. By adjusting the mouse's sensitivity to movement, you can make the mouse suitable for either bold or intricate artwork.

Kempston-compatible Art Studio is unfortunately currently only available with the bundled mouse package. Rainbird, however, is working on a Kempston version which will be available shortly.

The Kempston mouse is a fabulous drawing tool and a natural companion to Art Studio, but it can be used just for the mundane task of menu control.

The Writer, Softechnics word-pro pack, is widely proclaimed for its Kempston mouse compatibility - with one proviso: you must have a microdrive and Interface One.

Side 2 of The Writer cassette contains a Microdrive version of the word processor, together with its installation program. Installation on to cartridge is automatic after you've chosen to use keyboard or mouse and a version created for mouse will work with the keyboard but not vice versa.

The mouse has no effect until you enter the editor/menu modes by pressing the right-hand click button. You then use the left-hand key to select menus and the options within them. Again, the mouse saves time as you don't have to fiddle around on the keyboard or find specific control keys.

Unfortunately, Softechnics doesn't plan to make the standard versions of The Writer or The Artist - it's CAD package - mouse compatible. Artist II will, however, be out soon and it will be compatible with Kempston and AMX mice.

A sparse instruction leaflet with the Kempston mouse provides a minimum of information for getting it to work in Basic or machine-code programs. The mouse uses the In instruction to read its position in relation to the cursor on the screen. The X co-ordinate is read by in 64479;Y by In 65503. and the status of both click buttons is relayed. The co-ordinates are returned as eight-bit values corresponding to the relative movement of the mouse while the button is pressed.

A small Basic demo program is included in the notes but the process can also be applied in machine code.

Price: £69.95 Click Keys: 2 Sensitivity: software controlled Software Bundled - Art Studio Compatible - The Writer (Microdrive version only). Artist II

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Well designed but little software either bundled or available.