Fatigue tests were made on specimens having notches with very large fillet radii, and from the results of experiments, the following conclusions are obtained:
(1) The value of notch factor is not independent on materials, even when the fillet radii of notches are very large.
(2) In most cases, the value of form factor by Neuber is unreasonably smaller than the value of notch factor obtained by experiments in this report.
(3) The relation of Eq. (3), which is previously reported, is proved here to be appropriate for the calculation of form factor.

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In this succesive reprt we made experiments on the abrasion resistance of phenol resin in, the state of lubrication at various speed with the new abrasion testing machine specially designed, using tubular specimens. Phenol resin applied to tests was the laminate of canvas base which is the same as in the previous report, and experiments were also made on casted bronze for comparison. The specimens were rotated at the following four kinds of mean friction speed, that is 0.33, 0.45, 0.63, and 1.10m/s. Experiments were made till rubbing distance of about 28 kilometer, and amount of abrasion, frictional moment and temperature were measured. As the results, it was cleared that the abrasion resistance of phenol resin is very superior to that of casted bronze, excepting the case of low pressure and low speed.

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The plastic properties of a clay body pugged with a laboratory vacuum pug mill constructed by authors were measured by a torsion plasimeter. The results were compared with those obtained by the similar measurements carried out with the bodies of different clay contents, grain size as well as the different degree of aging, after they were pugged under atmospheric pressure.
The results may be summerized as follows:
(1) Through the vacuum pugging it is posible to obtain the body having such high workability obtainable only by the combination of fine grinding and aging.
(2) The decreasing grain size as well as the increasing clay content of a body are effective for the improvement of workability and in this case the plasticity runs parallel with the former.
(3) Although the evacuation and aging effect in favour of workability, the increase of the plasticity does not necessarily accompany with those.

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In the design of welded steel bridges, the fatigue strength of welded joints must be considered first of all. But in our country, there are no design specifications for welded steel bridges in which the fatigue strengths are taken into consideration.
For the purpose of contributing to the design of welded steel bridges, the author has performed the fatigue tests on butt welded and fillet welded joints.
This paper is a report on the test results, including (1) the author's emperical formulas for the endurance limits of the joints; (2) the allowable endurance limits for the same joints for our present welding technique, considering differences between shop and field welding and highway and railway bridges; and (3) the comparison between (2) above and the allowable endurance limits specified in other countries.

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Present paper explains the newly designed creep testing equipment, testing machine, automatic temperature regulator and apparatus for measuring creep strain, and exhibits some test results on lowcarbon steel. Discussion on the property of low-carbon steel at elevated temperature is added.

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