At the foot of Mt. Ôgi and Tsukuba in the Kantô District (Fig. 1), conspicuous development of gentle slopes is known, which have been vaguely considered as pediments, or pediment-like slopes. Gentle slopes are located at the foot of a fault scarp (Mt. Ôgi), at the foot of an old volcano (Mt. Myogi) or at the foot of a granite mountain (Mt. Tsukuba). It is the purpose of this study to assure if they are pediments or not.
The geology of Mt. Ôgi consists from north to south of Kobotoke group (Cretaceous), Katsuragawa formation (mid-Miocene) and Misaka group (Oligocene). Ôgiyama fault runs between the former two. On the Katsuragawa formation gentle slopes develop with a longitudinal range of about 100 m. Trans-verse profile is almost level at the upper limit of the gentle slopes, and undulated at the lower limit. Tops of undulation consist of harder Misaka group. The escarpment behind the gentle slopes coincides with the Ôgiyama fault scarp and this fact means that the gentle slopes were formed not by pedimentation but by rain wash and soil creep on the softer Katsuragawa formation during the course of slow elevation. Age the formation of the gentle slopes is concluded to be lower to uppermost Pleistocene.
To the northeast of Mt. Myôgi, gentle slopes develop on the Miocene bed and the escarpment behind the gentle slopes is the flank of an old volcano. Longitudinal range of the gentle slopes is about 300_??_1000m and the inclination is 5° _??_8°. Both the longitudinal and transverse profiles are undulated. There are talus deposits dropped from the escarpment. Formation of the gentle slopes occurred in middle Pleistocene.
Around Mt. Tsukuba gentle slopes are found in the coarse crystallized granite area, which is sometimes covered with fine crystallized granite or hard rock. Longitudinal range of the gentle slopes is 500_??_1500m and the inclination is 7°_??_12° . The gentle slopes are veneered by strata of cobbles, boulders and coarse sands, but in these strata bedding and sorting are not remarkable. The gentle slopes were formed by the parallel retreat of escarpment due to weathering, gravitation and rainfall, and modified by sheet wash, The age of the formation of the gentle slopes is middle Pleistcene.
Agreement on the origin of pediment is not yet obtained, and on the features of pediment there are many kinds of decription. For examples, the longitudinal profile of pediment is convex or concave; the escarpment end is straight or zigzag; and the transverse profile of escarpment end i s level, convex, concave or undulated. Picking up the common facts of all these pediments, the definition of pediments might be given as follows: the pediment is an erosional gentle slope with knickpoint at the foot of the escarpment behind, truncating the rock formations of the mountain ranges and developing continuously during the planation of mountain ranges.
Thus, it is concluded that the gentle slopes around Mt. Tsukuba are genuine pediments and those of Mt. Ôgi and Mt. Myôgi can not be identified as pediments.

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Some climatological aspects of the frontal zones at the ground and 850 mb-surface (Figs. 1_??_3) and the precipitation distributions (Figs. 4_??_6) from decade to decade in May, June and July over East Asia were dealt with. The following results were obtained:
(1) In the second decade of May, the rainy season appears in South China and the third decade in Japan. In the first decade of June, a marked frontal zone is formed from South China through East China Sea to the Pacific coast of Japanese Islands. Sometimes the frontal zone tends to disappear in South China, causing a pause of the rainy season. In the second decade of June, the frontal zone develops from the area around the lower course of the Yangtze River to the. Pacific coast of Japan; that is the beginning of the Mai-yü season over China and the Bai-u season over Japan. In the last decade of June it shifts slightly to the north. In the first decade of July, it runs from Middle China crossing over southern part of Korea to southwestern Japan. From the last decade of June to the first decade of July the rainy season reaches to its climax. In the second decade of July the frontal zone goes up further north. The rainy season ceases normally in this decade.
(2) The position of the frontal zone at the 850 mb-surface is deviated 2_??_6° latitudinally to the north from that at the ground-surface in the beginning period of the rainy season over China. However, there is no positional correlation over Japan and her eastern sea. In the climax period of the season the latitudinal deviation is 2_??_4° over China and Japan. In the last period of the season, there is no positional correlation over China and, on the contrary, 2_??_4° latitudinal deviation is found in the area around Japan and the Pacific. This change in the tendency of positional deviation of frontal zones between the 850 mb-and ground-surface over China and Japan can be explained in relation to the shifting of the jet stream in the rainy season.
(3) Characteristics of the precipitation distribution are analyzed only in the area over Japan and her surroundings. On the distribution maps of decadal precipitation from May to July one can observe always a zonal pattern along the Pacific coast of Japan (Figs. 4_??_6). On the other hand, the beginning of the season defined by the change in precipitation and the appearance of the maximum in the season shift from south to north (Figs. 7_??_8). The amount of maximum precipitation becomes smaller in accordance with the distance from the tonal area along the Pacific coast of Japan (Fig. 9). Therefore, it must be pointed out that the shifting of the frontal zone does correspond to the appearance of the maximum at any points and does not indicate the climatological distribution pattern of precipitation in the rainy season over Japan.

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This paper is concerned principally with the problem of sediment transported by the drainage system of three rivulets (Hayakawa, Fukôgawa and Ôkawa) in the northern extreme of Niigata prefecture. A detailed survey was conducted on these rivers and the information was collected during the period from. Aug. 20, 1959 to Oct. 30, 1959. The information includes sediment discharges, particle size analysis of bed load, water discharge and other hydraulic data.
The purposes of this report are: (a) to present briefly the results of measurement on the transportation of bed load by water during high stages and to provide some conception of the unknown volumes of sediment transported. (b) to feature the relative importance of the bed load of the rivers. (c) to examine the relationship between the actual rate of sediment transport and the sediment transporting capacity of the natural watercourses. (d) to check the several formulae for critical tractive force and for the rate of sediment transport under natural conditions.
Samples of the travelling bed load were collected with box type bed load sampler during high water stages. From these data, curves of tractive force τ versus bed load discharge Q_B, median grain diameter of bed load d₅₀, maximum grain diameter d_max, etc. were obtained respectively for each of these rivers.
From these curves fairy comparable relationships were found to exist between tractive force and other parameters. However, these curves suggest the existence of a sort of critical value, i. e. τ=4 kg/m², below which there is no consistent relationships between tractive force and other parameters.
In applying critial tractive force formulae to the natural rivers, d_max instead of d₅₀ agreed fairy well with the actual condition of movement of the bed load.

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It is a matter for great congratulation that, in the domain of Geomorphology, the scientific research in the true sense of the term concerning exogenic process has become active, especially with Prof. Hjulström's Brobdingnagian effort. Into the surface materials of the earth, however, so little investigation has been done by geomorphologists. In effect, the theory of rock control is not yet awakened from illusion in the prescientific state.
This article accentuates that geomorphologists should exert themselves with all their might to make scientific researches into the dynamic characteristics of the surface materials and into the problems which underlie these characteristics, on the basis of Quantum Theory of matter, Surface Chemistry, Colloid Science Chemistry, Colloid Science and so forth. Such scientific researches not only contribute to the remarkable development of rock control theory, but also they provide engineers with authentic informations and important data.
Finally, the writer advocates that we must give our students fundamental training of the said methods of research. Those professors and researchers who cannot and will not give this training ought to resign from their present positions. Leave their university voluntarily and that at once. That will be their most valuable contribution to the development of the theory of rock control.

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