Joe Brown

William M. Naismith was a Scottish Mountaineer who in 1892 developed a rule of thumb for calculating distances on a hiking expedition. This rule has become known as "Naismiths rule " and is thought to navigators all over the world.

In practice it turns out that Mr Naismith was quite a strong walker, and most people find themselves needing to add 25 to 50% to this rule to reach an accurate figure. As such, it can generally be assumed to be a minimum figure for time required.

 As the rule doesn't take into account fitness or fatigue levels, many variations of the rule have been developed. One of the most popular is known as "Tranter's corrections".

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Tranter takes into account fitness by including fitness. FItness level is defined as the length of time it takes a person to climb 300 metres in the space of 800 metres (1/2 a mile). Generally if you were doing these calculations in practice, you would have gone out yourself in advance to find out how long it takes you to complete the Tranter distance.

The fitness level in the first column is the time it takesyou to climb 300m in 800m and should be determined through a series of trials.

The following corrections to Tranter's Corrections should alsobe made for the following conditions

20kg load being carried - drop one fitness level
Conditions underfoot - drop one or more fitness levels according to conditions
Conditions overhead - drop one level for journey at night or if wind is against you