On the relation between the harvests of firseeds in Horo Experimental Forest in South Saghalien, where the fir is naturally distributed as its northern native region, and the meteorological elements which observed at Otiai Meteorological Observatory in 20 years, the investigation was practiced. The results are as follows:
1) As the differentiations of flower buds of the fir always occur in July or August in preceding years of the harvests, the carrelations of the harvest grades and meteorological elements in preceding two years were investigated. As the meteorological elements, monthly means of average air temperature, maximum air temperature, evaporation, humidity, amount of precipitation, velocity of wind and percentage of sunshine in every month from Janualy till August and moreover means of those meteorological elements in two or three months of May-June, May-July, May-Augst, June-July, June-August and July-August, were used.
2) There is no clear correlation between the grades (good and' average or poor) of harvest and maximum air temperature, amount of precipitation, amount of evaporation, percentage of sunshine, humidity, or wind velocity in preceding years. But there seems to be indistinct correlation between the grades of harvest and monthly means of average air temperature in July of preceding year.
3) Especially the correlation between the grades (good and average or poor) of harvests and minimum air temperature in preceding year iss found to be close. All 10 good (including average) harvests were happened when means of minimum air temperature in July, May-July, . May'August, June -July, June-August and July'August of preceding years were higher than 10.4°C, 5.4°C, 7.2°C, 7.7°C, 9.3°C and 11.5°C, and all 3 poor harvests were happened when means of minimum air temperature in these months were lower than 9.3°C, 5.2°C, 6.9°C, 7.3°C, 8.8°C and 10.6°C.
4) There is no clear correlation between the grades (good or; average) of harvest and meteorological conditions in preceding year. But there seems to be distinct correlation between the grades of harvest (good or average) and mean, maximum, and minimum air temperature in 1-4 months two years ago. All 8 good harvests were happend when means of mean air temperature in May July two years ago were lower than 11.5°C, means of maximum air temperature in May-July, May-August and July-August in these years were lower than 17.4°C, 18.8°C, and 23.2°C and means of minimum air temperature in these years were lower than 1.9°C. And 2 average harvests were happend when these air temperatures as related before were higher than 12.1°C, 18.0°C, 19.6°C; 24.0°C. and 2.4°C.
5) In the following years of good harvests, the harvests are always poor at any rate of meteorological, conditions in preceding two years, and those causes are expected to be related with storage of notirishments in the trees.

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Both the Hydrogen-ion concentration (PH) and the Iso-electric point (PHi) of the leaf of the “Witchs' Broom”-ed Paulownia were observed. The plant examined was an one year old tree which was artificially infected. The results obtained are showed in the following table.
Generally speaking, the PH-and PHi-values of the lamina and the petiole of the diseased plant become lower and their cr-values are smaller than those of the healthy.

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As methods of seasoning of wood, four methods were compared: (1) roasting method as usual in the case of retort, (2) adopting of roasting and simultaneous heating of wood with the hot gas generated by the charcoal gas producer, (3) simple direct heatig of wood with the hot gas generated by the charcoal gas producer, and (4) adopting of roasting and simultaneous direct heating of wood with the hot exhausted gas from the .fire-place.
According to the result, the most excellent one was the fourth. By this method, convection of air in the retort being promoted, much of moisture was rapidly carried off and the special fuel was unnecessary.

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1. The tension of cable wire can be obtained by this method correctly and promptly in comparatively simple way by the following formula. (See Fig. 1 a. b.)
T=w·l/4·h
2. The safety factor of cable wire was taken generally within 5, therefore if it was such a one as was used in this experiment, we use maximum tensions which are below 80 kg. In such a case the elongation of cable wire in the place of measurement of tensions will not become important to the result.
3. We can estimate the condition of tensions of the whole cable wire according to self-recording device e. g. Kymograph (See Fig. 2)
4. Accordingly we can estimate the tensions of every moment immediately after burden (load) departed from the end of the upper part. But the slightest change of “h” has much influence, therefore it is necessary to measure “h” correctly as far as possible.
5. As far the pulley of the part that requires measurement (B-Point in Fig 1) When its radius is not too small and has the least friction, the exact result can be obtained.
6. When we take “l” as above mentioned we can diminish errors of measurement by choosing “W” properly according to the circumstance.
7. when “l” and the weight of “W” are estimated correctly as far as possible, the exact result can be obtained. 8. Our method is convenient not only to examine tensions in operation, but also to verify intial tension of cable wire.
9. The application of this method is shown in Fig. 1. and θ=5°-6° that is, tan θ≅sin 8 is ideal.
10. The limit of errors of measurement is shown in formula (8) as following:
T-Wl/4h<W·h/2l

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(1) By the use of benzyl chloride on soda cellulose, or hydrocellulose, in the presence of alkali, a fibrous product results which is in soluble in all the usual solvents, its com-position approximates to that of a mono-benzyl ether C₆H₉O₄(OC₆H₅CH₃), di-benzyl ether C₆H₈O₃ (OC₆H₉CH₃)₂.
(2) The bonding strength of plywood by this ethers are shown in the following table.
Species of wood Test of normal state bonding strength Hot and cold soak test
Birch 145kg/in² 85kg/in²
Beech 121kg/in² 76kg/in²
Oak 118kg/in269kg/in²
Sen 120kg/in² 73kg/in2
(3) The bonding strength of wood and duralumin by this ethers are shown in the following table,
Species of wood Singl lap joint shear test
Sugi 36.5-38.7kg/cm²
Hinoki 54.0-55.6kg/cm² Beech 45.3-50.0kg/cm²

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The wood of Hinoki (thickness 1mm.) was acetylated at 30°C. with acetic anhydride, zinc chloride and acetic acid to decrease its swelling and shrinkage and the suitable conditions of treating time and additional weight of zinc chloride to 150cc. of acetic anhydride and 200 cc, of acetic acid were researched. The results of the study are as follows;
(1) The suitable treating conditions are indicated in the following table.
(2) The samples treated with above-mentioned conditions indicate increasing weight of from twenty and several to forty percent, and their effects of moisture-proof are ahrnyt three times as compared with untreated one.

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