Motions of saw mill operators which are different according to each function, were analytically investigated all over the working hours at a certain saw mill in Hokkaido Several motion elements were assorted from all motions about each operator and their time percentages against whole working hours were obtained: Figure 3 shows the percentage of net working time to whole working hours of each operator.

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The authors carried this study with woods of Quercus serrata Thunb.
containing various quantities of water, using iron retort of about 7 L. capacity. To obtain samples of various moisture contents, the woods were treated in three different ways, as follows;
(A) Woods were cut down and air-dried ud to such moisture contents as 40%, 30%, 25%, 10%, and less than 10% respectively.
(B) Air-dried wood of lower than 10% moisture content were dipped in water to absorb it fully and then air-dried again up to such moisture content as 40%, 30%, and 25%, respectively.
(C) Woods freschly cut down were soon dipped in water to absorb it fully.
The authors obtained the foollowing results in this study:
(1) In yields of the products of the destructive distillation on weight of the samples, charcoal, acids in distilled liquor (mostly acetic acid) and wood-gas (including loss) increased, and distilled liquor (including settled tar) decreased, according as moisture content of the samples decreased.
(2) But moisture content of the samples had not any effect on the yields of these products per weight of the absolutely dry samples.
(3) According as moisture content of the samples decreased, concentration of acids in distilled liquor increased.
(4) Volumetric gravity of charcoal was largest in the case of wood not air-dried after being cut down.(5) In the destructive distillation, water was distilled almost at 100∼150°C in the retort, the wood was decomposed gradually at 150-250°C and then temp-erature rised rapidly, much distilled liquor was run out, and much wood-gas was exhausted at 250-350°C. The wood-gas was composed of CO₂ and CO for the most part at 150-300°C, namely of about 60% CO₂ and 20-30 CO.

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The authors carried this study with woods of Quercus serrata Thunb. containing various quantities of water, usieg the Schrader's aluminium retort of aout 500 cc capacity. To obtain samples of various moisture contents, the woods were treated in the same way as formerly reported.
In this study, the suthors obtained the following results:
(1) Yields of the products of the destructive distillation on weight of fresh woods and the dried woods, and concentration of acetic acid in distilled liquor were the same in the case of the previous report.
(2) Volumetric gravity of charcoal was largest in the case of fresh wood not air-dried after being cut down and became smaller gradually according as moisture content of the wood decreased. But these facts were not obvious in the case of woods which were once air-dried up to lese than 10% in moisture content, and then dipped in water to absorb it and air-dried again.
(3) The course of the destructive distillation of wood could be divided into 4 stages distinctly. Water was distilled mostly at 150-200°C in the retort wall, distilled liquor and wood-gas were run out a little at 200-275°C, much at 275-300°C, and then distilled liquor again less and wood-gas comparatively much at 300-400°C.
(4) Distilled liquor at 250-400°C contained settled tar.
(5) Concentration of acetic acid was high in distilled liquor at 200-275°C but that of methanol was low. Methanol was contained much in the distillate at 275-350°C.
(6) So it would be supposed that in the former temperature range most of cellulose and in the latter temperature range most of lignin were decomposed.

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Results of some investigations about the amount of stream-flow from the watershed covered with forest in the deep-snow-district are reported in this article. The amount of stream-flow were measured with the self-recording-tide-gauge situated at the Simotakizawa in the College-Forest in the Omyojin village, Iwate prefecture. Meteorological factors were observed near the place. The observations were performed from 1931 to 1942.
After investigations the following are obtained.
1) The amount of annual precipitation and that of stream-flow are closely related each other. Tth correlation coefficient between the both amounts is 0.71.
The mutual relation is shown by the following equation.
y=0.71x-246.32(m.m.)
But after observation of the relation between the two (x and y) during seven months from June to November, it is found that the correlation coefficient is 0.91: that is to say, this is more closely related with the two than the other case. And the mutual relation can be shown by the following equation.
y=0.70x-231.81
(m.m.)
2) The precipitation which is most closely related to the stream-flow is not always that of the same month but that of the previous month or some other months before. The most closely related ones and the correlation coefficients between the two are as follows.
January VIII+IX+X+XI+XII+I 0.681 February XII+I 0.539
March III 0.464 April XII+I+II 0.711 XI+XII+I+II 0.717
May II+III+IV+V 0.902 Jun VI 0.790
July VII 0.965 August 0.944
September IX+X 0.661 October 0.920
November XI 0.941
December VII+VIII+IX+X+XI+XII 0.421
Note: The roman letters denote the months, when the amount of precipitation is observed. The greatest effect of melting snow upon the amount of stream-flow is observed in April, which starts from March to May, and very little in June.
They say that they will have plenty water for the irrigation in the coming year when they have much snow in winter, but it is clearly seen that the effect of the melting snow will limited by the end of May; the season for the rice nursery.
The stream-flow is caused by the melting snow by the end of May, so snow conserves the headwater compared with rain.
3) About the forecasting of the amount of stream-flow in the snow-melting season. The amount of stream-flow in April is greatly effected by the total amount of precipitation either from November or December to the end of February. The precipitation in April does not amount much.
The following equation will formulized betwen the amount of precipitation from December to February (x) and the amount of stream-flow in April(y).
y=0.6x-5.1
The forecasting for the other months is very difficult.

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The canopy-interception has been usually measured by the difference of the precipitation amount of two rain gage, one under the forest canopy concerned and one in the open. By this indirect method, true amount of interception is difficult to obtain on account of the ununiformity of precipitation under the canopy and the stem-flow being escaped. Another method of approach to the true interception amount which seems to surpass in exactness is to measure dirertly the maximum water storage of trees in the stand and evaporation during the storm. For this reason, as the component of canopy-interception, maximum storage amount of Pinus Thunbergii in the coastal forest of Chigasaki City, Kanagawa Prefecture was measured.
(1) The maximum storage of pine shoots were 0.27 mm in average for the crown projected area and under natural rainfall of 1-3mm per hour in calm conditions, water detention of the shoots attaind the maximum storage in 30-40 minutes.
(2) Pine has larger maximum storage and much water was sttached to the branch of the shoots than evergreen and deciduous broad leaves.
(3) The maximum storage of trunk and larger branches increased with di-ameter 0.01-0.09 gr per cm², and water attached to the larger branches and trunk was difficult to evaporate than smaller branches.
(4) The maximum storage of pine computed from those of shoots, branches and trunk was 1-1.3mm (for the projected crown area) in superior stands and 0.3-0.5mm in young trees of 50-100cm in height.

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Author introduced following three premises.
1. Each vascular bundle and wood parenchyma, which apear on the same cross section of bamboo stem, same properties.
2. Number of vascular bundle in same bamboo stem are constant.
3. Each spieces of bamboo have constant number and size of vascular bundle respectively.
Two theoretical formula were introduced from beforementioned premises and two empirical formula were got from experiments, and then induced mutual formula for physical properties -specific gravity (S) and Shrinkage in volume (λv)-and structural factores-thickness of bamboo stem(H), density of vascular bundl (D) and phloem ratio (B)-were induced.
Auther asertained that three premises were right or not, by compare induced formula with empirical formula, and can affirmed that preceding three premises in the right, as table 1.

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We observed the convection of a natural circulation kiln with a model by the “Schlieren Method”, to study the circulation in a dry kiln of lumber. Our observations were done on the next items.
1. Circulations varied with the setting of heaters.
2. Circulations varied with the position and sizes of the outlet ports. Results of these observations are as follows,
1. a) On the case of the level type, end of heaters shoulp of be set about 50 cmapart fromawall.
b) Mountain type and V type have not great differences in its effiency to co-rrect the heating current to the middle of a kiln.
2. Conditions observed on these items are I, (20×5mm) II, (20×10mm) III. (20×15mm) IV, (20×20mm); port Sizes; and in each case, the positions were changed 8 times on the wall from the bottom to the top.
In case of I, Normal circulation only
II, 11.1 11.5 normal circulation
II, II.6 11.8 reverse circulation
III, III..1 111.3 normal circulation
III, III.4 III.8 reverse circulation
IV, IV.1 IV.3 normal circulation
IV, IV.4 IV.8 reverse circulation

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