(1) It is found that pH of the Solution is suitable to be 4.0 to separate iron and aluminium as phosphate from much calcium. (2) 1 mol ammonium acetate buffur Solutin(pH 4.0) was used instead of the old method using a proper quantity of acetate. (3) Phosphate solution was added previbusly to preciptitate iron and aluminium as phosphate. (4) Hot 5% ammonium nitrate solution is used as the washing solution of the precipitate. (5) The effect of silicate and fluorine was examined and it was found to be necessary to remove them.

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The writer has found relationships among the NS-Quotients, the rain factors and the soil types in Japan, by considering the studies of Seki, Kamoshita, Swanson and others, and from the meteorological data obtained by the Central Meteorological Observatory, Tokyo. The relationships obtained are summarized in the following table : [table]Comparing the above-mentioned table with the results in Europe and the United States obtained by Jenny, it is understood that the NS-Quotient and the rain factor of each soil area in Japan are higher in figure than those of similar soil areas in Europe and the United States. This may be explained from the facts that the various soil types found in Japan are subject to heavier leaching than the corresponding soil types of other counries.

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The fact that protein content of wheat and barley is markediy influenced by the supply of nitrogen at later stags of their growth has been demonstrated by some investigators. The same trend seems to be probable for rice crop. So, I attempted to see to what extent the protein content of brown rice might be affected by the supply of nitrogen at later periods. Some of the preliminary experiments are reported in the following. Nine young plants, which were grown under the same condition, were planted in each pot June 13,1948 and cultured by nutrient solution. The nitrogen supply was stoped at two different periods : [table]Nitrogen determinations were made of samples at several periods of each set. The result of this investigation show that 300 mg. N per pot were absorbed by the plant after heading and 40% of this nitrogen were utilized for the increase of protein content in grains. The difference in the grain yield of the both sets, which were harvested at full mature, was not significant but the protein percentage of set (b) was 1.50% higher than set (a), corresponding to 5.90gr and 5.10gr are protein yield per pot respectively. As regards the quality of protein in brown rice the protein increase in set (b) run parallel with the increase of oryzenin, most common protein fraction in brown rice, the other fractions : albumin, globlin, prolamin and insoluble protein, remaining fairly constant.

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Buffer-index values of the expressed saps of roots. tap roots and tubers were investigated. The species of plants used in this investigation are as follows : Sweet potato, Carrot, potato, Barley Wheat, Rice, Coix laeryma Jobi, Stone-leek, Houttuynia cordata, Spinach, Worms seed, Broad bean, G. silvaticum. From these results, it seems that there is no correlation between buffer-index values and pH toterance around pH 4.6-4.8,but the buffer-index values at pH 6.4-6.6 for alkalitolerance are higher than for acidtolerance in general. This subreport makes no claim to be complete, or widely based or conclusive; but there is enough to make a case for more general attention and more detailed examination of these phenomena.

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A kind of Vacuum Tube Potentiometer for determining pH or Eh of soil and other substances using ordinary Radio tubes (KX 12F and UZ 6C6) and a hady Spiring Ammeter is devised. A slight change on the grid voltage due to potential difference desired affects a considerable change of plate current by socalled A-class amplification. This change on the plate currcent canelled by a compensating potential difference. This compensating potential difference is read directly by a Voltmeter, the foregiven Ammeter being used. Usages and notices are given.

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ln this papar the author investigated the types of humus of paddy soils by the Simon's method. The results are summarized as follows : (1) Humus extracted from the paddy soils (fallon slice) using NaF or NaOH solution was generally composed of humuc acids (rotted materials and true humic acids; 60-70 per cent) and fulvic acids (40-3) percent). (2) Humic acids were chiefly rotted materials, which conld be extracted only by NaOH, Besides, in case of the dry paddy soils, there were true humic acids equal to the amounts of about 30 percent of rotted materials, mainly cxtracted by NaF(On the other hand, in case of the wet paddy soils, true humic acids seemed not to exist. (3) Because of the fact that our rotted materials ad higher humification values than Simon's so-called rotted materials, further investigation is neccssary to characterize these humic acids.

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