WE RECENTLY heard from a reader who was dismayed that an airline would not allow him to carry a large diving knife in his hand-luggage. He was going to the Maldives and, as he had heard that there were lots of sharks out there, he did not want to go unprotected.
A knife will do little to prevent shark attack. We should like to dispel two myths peddled by a sensationalist film industry - sharks do not regularly attack divers and diving knives are not weapons.
The fact that many diving knives look ideal for taking on grizzly bears is more reflective of the macho tendencies of those who buy them than their usefulness. The most serious hazard a diver is likely to meet underwater is entanglement in net or line, so one could even argue that a pair of scissors is preferable to a knife. Most knives in the directory have both a slicing and a serrated edge to their blades.
The traditional hard-hat diver carried a large Siebe Gorman knife around his chest so he could cut his tethering rope if it got caught up in the wreck he was working on. Modern diving knives have evolved from those days.
When choosing a knife, be sure to look for a secure holster. Lost knives are often found on the seabed because they were stowed incorrectly after use.
Diving knives are usually made from stainless steel, but this does not mean they will stay rust-free. It depends on the grade of steel- the more rust-resistant, the more brittle the blade and the less inclined it is to take a sharp edge. A good knife needs to be rinsed after use and must be well-greased to avoid decay.