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Chalk - is it useful? 25-Dec-2012 At 9:42:40 PM Jim Titt

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Once you get past kindergarten you´ll find that the first thing you read or were told may not actually be true, for example Father Christmas may not exist despite what you learnt at that formative age.

Extending your reading horizons you´ll find further scientific reasearch on the matter performed to a considerably higher level such as;-

"The effect of chalk on the finger-hold friction coefficient in rock climbing"

Authors: Amca, Arif Mithat1; Vigouroux, Laurent2; Aritan, Serdar1; Berton, Eric2

Source: Sports Biomechanics, Volume 11, Number 4, 1 November 2012 , pp. 473-479(7)

Abstract:
The main purpose of this study was to examine the effect of chalk on the friction coefficient between climber's fingers and two different rock types (sandstone and limestone). The secondary purpose was to investigate the effects of humidity and temperature on the friction coefficient and on the influence of chalk. Eleven experienced climbers took part in this study and 42 test sessions were performed. Participants hung from holds which were fixed on a specially designed hang board. The inclination of the hang board was progressively increased until the climber's hand slipped from the holds. The angle of the hang board was simultaneously recorded by using a gyroscopic sensor and the friction coefficient was calculated at the moment of slip. The results showed that there was a significant positive effect of chalk on the coefficient of friction (+18.7% on limestone and +21.6% on sandstone). Moreover sandstone had a higher coefficient of friction than limestone (+15.6% without chalk, +18.4% with chalk). These results confirmed climbers' belief that chalk enhances friction. However, no correlation with humidity/temperature and friction coefficient was noted which suggested that additional parameters should be considered in order to understand the effects of climate on finger friction in rock climbing.

Or
"Instrumented Climbing Holds and the Dynamics of Sport Climbing" by Fuss/Niegl published in Engineering of sport 6 Vol 1

Which comes to essentially the same conclusion with an increase in friction of 32% with loose chalk and a decrease in friction of 8% with wet hands on artificial holds.

Both of which coincide with the experience of millions of climbers worldwide.

Merry Christmas to you too!