By John Lippmann. Aqua Quest Publications

Price £16.95 YOU PAY ONLY £8.95 (+ £2.50 p&p*)

An authoritative book on the physiology and requirements of deeper diving, defined as ranging from 24m (80ft) to 40m (130ft). Born from a concern that divers are venturing deeper than ever before due to changing technologies, the book tackles nitrogen narcosis, tables, computers, dive techniques, use of mixed gases and more. The text is geared for divers of all levels of experience, and illustrated by black and white photographs and tables. 180mm x 255mm softback. 320pp.

*p&p applies to UK and BFPO addresses only; for overseas rates call +44 (0)20 8941 8152.