The relationship between force level of isometric contraction and time of three indices of muscular fatigue was studied for the shoulder abductors, elbow flexors, elbow extensors, knee flexors, knee extensors, plantar flexors and dorsiflexors in 5-7 males. Endurance tasks were performed at the contraction levels of 5, 10, 15, 20, 30, 40 and 50% of the maximal voluntary contraction (MVC). The relative force (F%MVC) versus the endurance time or the time of tiredness ("darui") and pain ("itai") appearance (T min) curves were fitted to the following equation; logT=a+blog(F-k), 0_??_k_??_30.The most fitted equations were determined by the value in the coefficient of determination. In the examined muscle groups, the shoulder abductors were the most fatigable. The least fatigable were the plantar flexors and dorsiflexors, followed by the elbow flexors. The knee extensors were fatigable at higher contraction levels, and relatively fatigueless at very low contraction levels. The knee flexors, which were relatively fatigueless at higher contraction levels, became fatigable at lower contraction levels, where they showed similar fatigability as the elbow extensors.

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The objective of this paper is to illustrate a method for estimating the number of simultaneously occupied dwellings in a site, and to test it by applying it to Jomon settlement data. Data are taken from 51 Early Jomon sites of the Moroiso pottery stage (ca 5000 B. P.) in the Kanto district. All the Moroiso stage dwellings in each site are divided into six sub-stages based upon Moroiso pottery sub-types. 88 percent of all the cases analyzed in the paper are found to be composed of between one to four dwellings per sub-stage. The dominance of small occupations is apparent in all six of the Moroiso sub-stages. This has important consequences for studies of Jomon population and sedentism.

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A new apparatus of moiré iso-hypsigraphy was designed and produced to examine relatively small materials such as human skulls, innominate bones and scapulae. The parallel light source method producing moiré fringes was adopted, which is much appropriate for the small objects. The reflected light, furthermore, was considered, because moiré fringes produced by the parallel light needed to be recorded by the camera system in condition of nearly parallel reflected light. For recording system a 35mm camera with a 800mm focal length lens was selected. In this system one can measure the photographs with moiré fringes under the permissible error, i. e. 1%. Moire producing parts of an apparatus has many improvements for the small objects: condenser lens, field lens, reflecting mirror and threads in grating. In the apparatus the skull fixer and co-ordinates indicator, in particular, were specially designed. By them the skulls on which the moiré fringes are produced can be fixed in the Frankfort horizontal plane. In the photographs of them the moiré fringes on the skull will indicate coronal sections as exact equal contours.

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