The experimental study of pitch trouble described in report 7 was followed up by another serieE of experiments using the same apparatus : several sorts of pitch prepared by mixing up two or three different substances in various proportions were used;the changes produced by cooking in the property of resin from the sap and the heart wood of pine (Pinus densiflora) were examined;resin from the cedar (Cryptomeria japonica) was tested as to its bearing on pitch trouble.
10) The wire-attached proportion was 75% or so for a mixture of saturated fatty acid-a substance incapable of causing pitch trouble by itself-and an oil containing an ester of unsaturated fatty acid in large quantity;it was not so large as to cause pitch trouble for a mixture of saturated fatty acid and a substance containing an ester of the acid, as coconut oil, Japanwax or rosin.
11) The wire-attached proportion was generally 70 %-a percentage suggestive of pitch trouble for a mixture of an oil containing saturated fatty acid or its ester and a-pinen, p-cymen, or turpentine oil.
12) Rosin, a-pinen, p-cymen and turpentine oil caused no pitch trouble when used separately, but a mixture of rosin and any of the three cgher substances had 80% of its volume attached to the wire and caused a serious pitch trouble, probably because the essential oil content acted as dissolvent and increased the viscosity of the mixture.
13) A mixture of pitchabietic acid (70%), an oil-type substance and an essential-oil-type substance -a mixture closely similar in composition to pitch-had 85 to 96% of its volume of wire-attached proportion and caused a serious pitch trouble.The use as the main content (70%) of the mixture of rosin or saturated fatty acid, instead of pitchabietic acid, resulted in the production of a pitch trouble no less serious, The wire-attached proportion was reduced when the pitchabietic acid content of the mixture was reduced from 0.2 to 1.0g (11 to 50 %), , It was seen as a result that pitch trouble was severest when the volume of pitchabietic acid constituted the 70 % of that of the whole mixture and the remaining part was a mixture of an oil and resen or an essential oil.
14) Sapwood resin and a mixture of sapwood resin and unsaturated fatty acid caused no notable pitch trouble, but for cooked sapwood resin the wire-attached proportion was 89%, for its mixture with pitchabietic acid or with knot resin 80%, for heartwood resin 88%, -each a percentage suggestive of a serious pitch trouble-for cooked heart wood resin, as for knot resin, it was too small to cause any pitch trouble.
15) The wire-attached proportion was 3 % or less for pitchabietic acid and for resin acid from heart-wood cooked.
16) The wire-attached proportion was small for cryptopimaric acid, resin from a ceder resin and ceder wood resin, 39% or less-a value not suggestive of pitch trouble-for a mixture of any of those substances and pitch, unsaturated fatty acid, or resen, and 60 % for resin from a cooked mixture of pine wood 8 parts and cedar wood 2 parts, so that the cedar wood reduced the severity of pitch trouble.

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The idea of high pressure on shower pipes is not new but practical application does not yet.There fore, we examined a spraying test by Emerson Shower Pipe at Asahi Iron Works Co., in order to determine what effect the high pressure spray have on washing.
From this test, we found that the using of high pressure saves a consumption of fresh water as compared with the using of conventional low pressure.Thereto, it can be estimated that the washing effect of spray on high pressure is approximately proportional to the water speed (U²) and the quantity of the spray (Q), whereas a washing effect can be computed as (U²·Q).

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I reported the chemical compositions and the quality of cellulose of the stalk of rape-seed and concluded that it was simillar to the stalk of cotton.So in this paper, to utilize it, I attempt pulping of it by sulphate method.In the case of 26% sulphidity and 25% total alkali, pulp is easy bleach and lower yield (43%).But in the case of 26% sulphidity and 17% total alkali, pulp is : strong, deep colour, difficult to bleach and high yield. (48%).
In the case of 13% sulphidity, even 20% total alkali, pulp is very easy bleach.
Generally rape-seed pulp is easy, to wet beating and as strong as hardwood pulp.

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