Attempts have been made to propose a quantitative analysis of the relation between the productivity and the degree of opening, which is closely related to the arrangement of carding points and the operating conditions of a card. The following two assumptions were made to solve the problem easily; (1) a fiber tuft reaching a carding point is simply divided into two smaller tufts so that the proportion in weight of these tufts is equal to the value of the transfer coefficient, and (2) the degree of opening of web can be estimated by the mean value of logarithm of reciprocals of the weight of delivered tufts.
The distribution of delivered tuft weight, the distribution of the number of passings through the carding point and the degree of opening have been derived as the function of the transfer coefficient by these assumptions.
Then, taking account of the experimental results that the productivity is restricted by the fiber load on the cylinder from the standpoint of nep formation, the relation between the degree of opening and the productivity has been discussed.

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First, a way of determining the distribution function of fiber-end positions by the sliver thickness which can be easily measured is discussed, and it is shown that the distribution function can not be detected by the sliver thickness except points which are located at interva ls of the fiber length. Next, a new method is proposed to detect the distribution function of the fiber-end positions at intervals of 1/N times longer than the fiber length by measuring and comparing the sliver thickness before and after drafting, if the drafting ratio used is expressed by a reduced fraction N/M(>1), where M and N are integers. So, it becomes possible to control the very short range irregularity of the sliver thickness theoretically.
The elemental interval defined in this paper is the length T/R, where T is the whole length of the sliver and R is the total number of fibers. The standard dispersion calculated from the series of the number of fiber-ends contained in each elemental interval is assumed as a representative index of the irregularity of sliver thickness. However the elemental interval is usually so short that such a length as n times longer than the elemental interval is used for practical observation. Then, a method based on the maximum entropy principle of information theory is proposed to estimate the standard dispersion for the elemental interval from data by the observation interval and to predict the irregularity of the sliver thickness after control. By applying this method to a random sliver, the expected thickness irregularity controlled by an ideal draft mechanism is investigated.

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In order to clarify the fluttering behavior of flexible bodies in a stream, the wave form was assumed as y=ax•sin(pt+qx), and from the energy conservation principle, p and q were determined as p=-0.415V√<(ρ/ρ_s; )(b/l)(C_x; +2k₀; )> q=1.6911/l
On the other hand, fabric or film strips were observed in a vertical wind tunnel, and it was shown that the wave form assumed agreed with the observed form within a limited range, and that the frequency calculated from the above-mentioned p could give the rough estimate of the real flutter frequency.
However, the wave form observed was very complicated, and especially so at the tail part of the strip.

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A new wool scouring system which can take place of the conventional type has been developed. Its main characteristics are(1) the use of a pipe as a scouring bowl in which wool fleece is scoured by a stream of washing liquid, and(2) the use of air flow for the agitation of wool and liquid in the pipe.
This article describes the mechanism and the scouring principle of this system and some experimental results. The main conclusion from experiments using a medium-scale test equipment is as follows; (1) Although some minor problems are left unsolved, this new system can be put into practical use as an improved wool scouring system. (2) The composition of the scouring solution and the treatment time with this method are the same as those with the ordinary method. The most appropriate air flow rate per unit time is about one fifth of the liquid flow. It should be large in the first bowl and then be gradually decreased as the wool is scoured. (3) The inclination of the pipe should be as large as possible. In the test reported here no problems occurred with tilt angles up to 8°30', which was the highest used. (4) The equipment is suitable for many uses. For example, continuous materials such as sliver or fabric pass it through smoothly without being stretched, twisted or jammed. It is therefore possible to use it for continuous wet treatments.

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