When the fibres slip through the pads the flow of liquid is stopped and the volume of the ruoff liquid is measured; a preliminary calibration of the apparatus enables the clinging power to be calculated from the volume of the liquid collected in the measuring cylinder; the liquid used for this purpose is a solution of calcium chloride having approximately the same vapour pressure as that of th [...] However at the breaking place the number of fibres will normally be decidely less than the average of the whole length of yarn and so we reach the conclusion that with an effective load of 72 grams the pressure exerted by the friction pads is in the neighbourhood of that experienced by the fibres of a yarn subjected to a breaking test. [...] He does not give the actual average load required to pull a single fibre through the friction pads nor does he give the value of the effective load producing the pressure between the pads; the results for the load required to pull a single fibre through the pads are given only in terms of the water withdrawn to cause slip." For the five different types of cotton tested the average values obtaine [...] Again the frictional resistance of a yarn to tension depends on the number of fibres in the cross-section and as the clinging power is expressed as per fibre (or group of io fibres) it follows that in order to obtain the frictional resistance of the yarn to breakage we must multiply the clinging power per fibre by the number of fibres in the cross-section this number being inversely proportiona [...] The magnitude of the coefficient of variation is an indication of the spread" of the values; thus the "spread" is greatest for the highest standard warp counts large for the fibre-weight per inch and least for the fibre-length.
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