The three books Brainteasers, Micropuzzles and 101 Puzzles To Solve On Your Home Computer provide a good cross-section, both in state-of-the-art puzzle books, and in computer book publishing. In no case does the price of the book generally provide any accurate guide to the quality of the contents. I shall begin with the least expensive and work upwards.

Micropuzzles is part of the Pan PCN library - a series launched fairly disastrously last autumn. Since then two titles have had to be pulped because of the extraordinary number of errors, and no-one is very happy with what's left. Micropuzzles is probably the best of a bad bunch. It consists of a straight reprint of the puzzles set by JJ Clessa over the years in the 'Leisure Lines' feature of Personal Computer World.

You get 144 pages for your money. The first part of the book consists of seventy 'quickies' - so named because you are expected to solve them in your head or employ a little lateral thinking. Mos of them are rather well known - e.g. 'What weighs more, a pound of features or a pound of gold?', a puzzle I recall reading in the Reader's Digest when I was about siz - and who knows where they got it from! I cannot see the point of including this sort of thing in a 'computer library'. Unless, that is, you need to pad out a book!

For the record, there are sixty puzzles that are soluble by computer, though in several cases the author says that doing it logically with pen and paper is more efficient! One hopes that Pan, arguably the most impressive and professional of UK paperback houses in most areas, will take rapid steps towards improvement.

101 Puzzles To Solve On Your Home Computer is the best-produced of this tro. It has the largest format of the three - A4 size - and each question is accompanied by a cartoon. A nice touch is the spiral binding, which enables the reader to leave the book lying open while constructing a program to solve the problem. It I have a criticism it is that the author has found it difficult to make all his puzzles original: he ingeniously sidesteps this point by dedicating the book to Lloyd and Dudeney, the most creative people ever to construct puzzles. And, it must be admitted, coming up with 101 new ideas would stretch the ingenuity of most people.

It's no coincidence that the famous problem about the five castaways, the monkey and the coconuts - an ideal problem for a computer - appears both in Clessa's book and in this one. Still, they're in good company. Last summer, The Sunday Times Brainteaser, normally rather an original source of intellectual stimulation, used it.

Andrew Hilton has done a good job in sorting his puzzles into number-crunchers, problems involving the use of nine or ten different digits once only, exercises in probability and codes and ciphers. His book probably represents the best value for money of all three.

Brainteasers at £9.95 is the most expensive; its author claims to specialise in marketing educational software. Instead of a series of puzzles with answers at the back, this book consists of a series of games that you type in from a listing of a BASIC program. The publishers have sensibly printed the listings directly, rather than entrust them to a typesetter, but they used a cheap printer, so the result is messy and difficult to read.

The games are the kind that interests people new to the excitement of computers, but most of us grow tired of this sort of thing within a couple of months. In fact, most Acorn User readers would be likely to spend more time fathoming out the listings and typing them in than in actually using the software. Still, the enthusiast can save the trouble by sending another £6.95 to the publishers and getting a cassette of the programs. At twice the price of the Pan book, and the same number of pages, this bok is really a bit expensive.

Simo Dally