The relation between the magnitudes of instrumental measurement and subjective assessment of the surface topography of three series of plain weave, weft pile and knitted fabrics is reported. It is found that the surface feel of fabrics is influenced by the number, height and relative variation of surface asperities. In woven fabrics, a systematic increase in yarn sett greatly altered the peripheral boundaries and hence smoothness of fabric surface. The tactile smoothness of cord fabrics is influenced by the number, height and variation of heights of the fiber piles. Surface fuzziness and number of detectable ribs appear to govern the smoothness of knitted fabrics. Magnitude estimation and surface contour causal factors such as number and height of irregularities correlate linearly.

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The flow field in a yarn duct of an interlaces is clarified by measuring pressure distributions on the yarn duct wall and flow velocity distributions near it. An enlarged interlacer similar to a practical interlacer has been manufactured on the basis that the flow fields in two similar interlacers in geometry are also similar in fluid dynamics. In this manner detailed measurements can be made and data with high accuracy can be obtained. Results are as follows:
(1) With regard to the axial direction of the yarn duct, the pressure h_s takes the maximum near Z=0 and the minimum near |Z|=1, where Z is the axial distance from the center of the air jet nozzle non- dimensionalyzed by the diameter of the yarn duct. The value of h_s gradually increases with |Z|, and is identical with the atmospheric pressure at |Z|=2. The above- mentioned tendency is independent of θ and p in the present experiment, where θ is the circumferential angle in the yarn duct from the center of the air jet nozzle and p is the air pressure in a rectification tank.
(2) The variation of h_s with respect to θ depends upon Z. In Z=0 the value of h_s is extremely large at θ=180 deg and reaches the minimum near θ=90, 270 deg. In Z=1 it shows a considerably small variation, and a negative value in almost all regions. In Z=2 it is almost constant and nearly equal to the atmospheric pressure.
(3) Compared to the air pressure in a rectification tank, the value of h_s is nearly equal to the atmospheric pressure in almost all parts of the yarn duct wall.
(4) The air jetting from the air jet nozzle radially spreads along the yarn duct wall after running against the wall opposite to the air jet nozzle. The air with a circumferential component of flow velocity flows along the curved wall, and two eddies are formed which are symmetric with respect to the plane through θ=0, 180 deg and rotate in opposite directions to each other. With increasing |Z|, the circumferential component of flow velocity diminishes and the axial component is dominant. The main flow moves from the periphery of the yarn passage to its center. With respect to the circumferential direction of the yarn passage, the flow is biased toward the semicircular region nearer to θ=180 deg.
(5) The present experiment shows that the air flow pattern in a yarn duct is independent of p.
(6) It is considered that the air jet causes not only opening and tangling behavior of a yarn in the region (|Z|< 1/2) where the jet directly runs against the yarn, but a yarn motion similar to rotation in the region (|Z|<1) where the circumferential component of flow velocity is relatively dominant.
(7) Since errors in manufacturing interlacers have an influence on the flow field in a yarn duct, they are considered to cause yarns with various characteristics even when the processing conditions are common among interlacers.

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Systems of instrumental method for measuring fabric hand have been successfully developed like KES and its basic way has been well established. On the contrary, systems of sensory method have been remained to be at a controversial state.
In this paper, a practical sensory method is proposed on the basis of analogy to sensory colorimetry. Measuraneaa of two kinds of worsted fabrics was conducted by making use of this sensory method. The effective range and the accuracy of this method are discussed based on the data of the above measurement.
As a result, it is shown that if a suitable control (temporary standard) sample is chosen, the instrumental values of bending rigidity, thickness and compressibility of worsted fabrics can be estimated by this sensory method with the error of around 20%.

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