Even where there is enough rainfall with proper seasonal distribution, every few years dry spell upsets nature and crop is lost. In such a year farm irrigation is very effective.
Our experiment was made in summer of 1953 under unfavorable weather conditions using an upland rice at the field of Tokyo University of Agriculture and Technology, so as to clarify the effect of farm irrigation. We could not get good results to demonstrate the effectiveness of the farm irrigation from our experiment, but designate the differences of soil water content and soil constitution between the irrigated plot and the cultivated one, as shown in Fig. 3.

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We have made further experiments after our previous one in 1952 on lots shown in Fig. 1 in order to test the significant difference of baido types and the frequency of baido operations with special reference to the mannure conditions.
The soil temperatures were observed once a day at 10th every morning as in the former experiments.
The difference of the soil condition during the cold season can be seen among these form plots, but there is no significant amount of variations in the grain yields by use of the lot as in 1952, except that the influency of mannure conditions in seen.

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1. After the copulating moths of Antheraea pernyi had been kept under various temperatures viz. -2.5°C, 2.5°C, 5.0°C, 10.0°C, 15.0°C, 22.0°C, and 25.0°C, 3 hours respectivly, they were examined when spermatozoan reached the copulatory pouch and the seminal receptacle in the female body.
a) The spermatozoa did not appear in the copulatory pouch and the seminal receptacle under the temperature of -2.5°C, 2.5°C, and 5.0°C. Probably it depended on the incomplete ejaculation or on the immobility of the sperm in such low temperature, but there was only one case in which the spermatozoan were found in the copulatory pouch not existing in the seminal recepacle.
b) The spermatozoa were found in both the organs under the temperatures of 15.0°C, 22.0°C, and 25.0°C.
2. After the eggs of this moth had been kept under various temperatures viz. 2.5°C, 5.0°C, 15.0°C, and 25, 0°C, the hatching ratio was observed in different elaps of time viz. 1, 2, 3, 5, 20, 30, 60, 90 and 120 days. In this experiment the ratio showed 92.1% in 15.0°C, and 91.7 in 25.0°C, but the eggs kept for 10 days in 2.5°C and 5.0°C did not hatch at all.
3. After the oviposited eggs had been kept under various temperatures for relatively short times viz. 3.0, 5.5, 9.5, 15.0, 20.0 hours and 1 to 10 days, the hatching ratio was observed. In this experiment it showed that 1 to 3 hour exposures to the low temperatures such as -2.5°C to 5.0°C were not effective, but the ratio became very low in the exposure longer than 5.5 hours and it fell down in the exposure of 10 days.

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In order to establish the method of early estimation of the yield of sweet potatoes, the anther analysed the results of the experiments of meteorological influences, which were carried out at Ono Town, Nakagun, Kanagawa Prefecture from 1948 to 1952.
1) The crop of sweet potatoes increase with high temperature from May to July and in September, and by much rain in August.
2) Analysing the process of growth in each month, and examining M, σ and V among 10 meteorological elements in each period, the fast is found that the order of good time for yield estimation is June, July, May, September, October and August, and that the order with respect to the meteorological elements is 1, 6, 7, 8, 5, 3, 2, 10, 9, and 4.
1. air temp. at 10hr. 2. max. air temp.. 3. min. air temp. 4. precipitation 5. temp. of soil surface at 10hr. 6. soil temp. of 5cm depth at 10hr. 7. soil temp. of 5cm depth at 10hr. 8. max. soil temp. of 5cm depth 9. min. soil temp. of 5cm depth 10. soil temp. of 10cm depth at 10hr.
3) By the order. the most important meteorological element in each process of growth can be made clear.
4) The difference of the coefficient of correlation of each meteorological element to yield between adjoining month is the greatest is July and August, little in May and June, and in June and July.
5) The corpulence of sweet potatoes is parallel to the passage of calendar days. But when we observe the process of growth, we find that in the early stage of growth, the yield is closely related to the number of leaves, the number of potatoes, and the weight of potatoes, in the middle stage to the weight of stem, in the letter stage to the weight of potatoes.
6) To estimate the yield July 15-April 1 is the fittest, which can be said of the number and of the potatoes, the length and weight of the stem, and the number of leaves in common. All through the process of growth the correlation of both length and weights of the stem is highly fitted.
7) We can further confirm above results by the method of analysis of variance. Then we formed 19 expressions for estimating yield based on these facts and compared the estimated value with the observed value. The results were as follows.
The C. V. was less than 2% in 6 expressions (19, 16, 14, 17, 5) and 2-3% in other 10 expressions except expression 1 (6.4%).

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1) The approximate daily mean temperatures may be obtained by means of three or four observations a day at equal time-intervals. As the routin work in cultivating season, the observations of daily extremes of air-, water-, and soil-temperatures are the most convenient.
2) The averaged temperatures of the soil-strata may be easily deduced from the mean soil-temperature at 10cm depth, (See Fig. 2 and Table 3)

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(1) 関東地方に於ける昭和28年産小麦に発生した凍霜害の樣相には全く異つた2つの型があつた。
(2) 1つの型は出穂開花期に百葉箱内気温が0℃以下の低温となつたために不稔穂又は損傷穂が多発して減収となつたもので千葉県の北部地区に見られた。
(3)他の1つの型は幼穂伸長初期に百葉箱内気温が-1℃以下の低温になつた為に幼穂枯死茎が多発して有効穂数が減少したもので栃木県の北東部に見られた。

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By the Kizia typhoon visited on Sept. 13. 1950, the late rice plants just in the earing date were most seriously damaged.
The results investigated to know the damages done by this typhoon on rice grains are summarized as follows:—
1. Small brown discolored spots appeared on the surface of rice grains especially in late rice plants just in the earing date.
2. These damaged grains contained more green (unriped) and incomplete kernels but less complete, and into the bargain some brown kernels. But no deformed kernels were observed,
3. Weight of 1, 000 kernels of damaged grains decreased about 5%.
4. These damages to grains were a little seriously observed in the glutinous rice than in the nonglutinous.

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Agro-meteorological study on the locality of the summer cool damage was tried in Iwate Prefecture, as a sample, where the summer cool damage of paddy rice is most remarkable in Japan.
Fig. 1 shows the locality of the summer cool damage, based upon the yield.
right: The towns or villages, where the summer cool damage occured most frequently. In these towns or villiages, the bad harvest (the yield of paddy rice decreased less than 80 of normal crop) occured more than 30 in probability.
left: The towns or villages, where the cool summer damaged the crop most severely. In these towns or villages, the yield in the cool summer year (1931, 1934, 1935 and 1941), always were less than 70 of normal crop.
Fig. 2 shows the locality of the summer cool damage, based upon the agro-meteorological data (number of days in July and August, when the daily minimum temperature are less than 15°C).
right: The districts, where the summer cool damage occur most frequently. In these districts, the cool summer (i. e. number of days, when the daily minimum temperature are less than 15°C, are more than 15 days in July and August) occurs more than 30% in probability.
left: The districts, where the cool summer damages the crop most severely. In these districts the cool days (daily minimum temperature are less than 15°C) occur more than 9 days in July and August, on the avarage.

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Some micrometeorological properties were observed in large practical frames that were covered respectively with vinyl film, glass and oil paper. From Table 1, 2 and Fig. 2, 3, it is recognized that the existence of two active surfaces (surfaces of the ground and cover of the frame) and physical qualities of the covers have the significant effect for the micrometeorology in the frames.

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In this report the writer treated mainly the following problems on the small model frames:
(a) Change of covers transmissibility for heat radiation with solar elevations (Table 1).
(b) Relation between the position of straw-mulching layer and the night temperature in the frame (Fig. 3).
(c) Diurnal variation of the relative humidity and vapor pressure in each frame (Fig. 4).

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The author set up the equipment, as was shown in Fig. 1, fixing the newly constructed tin receiver to a two or three year seedling of Japanese black pine planted in a pot.
And the amout of the stem flow and rain falling through the crown was measured at every shower and the rate of rain falling through the crown was calculated.
(1) In case of the three year seedling, the rate of rain falling through the crown was 40∼50per cent in case of 1mm of the precipitation.
(2) The rate of rain falling through the crown gradually increased with the precipitation nearly up to 5mm, but when it was more than about 5m.m. this rate seemed to be constant by 90∼95per cent.
(3) In case of two year seedling, the rate of rain falling through the crown was greater than that of the three year seedling and it was 60∼70per cent for 1m.m. of the precipitation.
(4) In general, the rate increased with the precipitation nearly up to 3m, m, every shower but when it was more than 3m, m, it was about 90∼97per cent.

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We observed the micro-climates in two citrus-orchards different only in the tree density, in the summer of 1953.
Fig. 1 shows a continuous record of insolation in two orchards, thickly or thinly wooded, for two days. The total insolation in the thick orchard is only 63% of that in the thin one.
The daily march of humidity is shown in Fig. 2, where the relative humidity in the thick orchard is lower than that in the thin one, in the day time, The vertical distributions of temperature under the crown are shown in Fig. 3.
In the thick orchard, the outer active surface and with it the temperature maximum consequently is located near the top of the crown.
On the other hand, in the thin orchard, the outer active surfaces are located rather below the crown surface and also the ground surface.
Fig. 4 show the daily march of soil temperature at various depths within the ground and afford contrast between the thick and the thin orchards.

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Using the apparatus of Fig. 1, authors measured the amount of evaporation from the irrigated paddy field and absorption (≅transpiration) of water by the paddy rice in each growimg period 1953.
These results are shown in Table 1 and Fig. 2. The absorption were few at first and reached to maximum in the beginning of young panicle formation. The evaportion in the paddy field were nearly equal to the evaporation at the observation field at first, but the former had been gradually less than the latter.

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In a paddy field, solar radiation is absorbed not only by the soil surface, but also by the covering water. So, we must take into consideration “Absorptivity of paddy field” which includes the absorption by both soil surface and water, but not the reflection.
In this paper, absorptivity of paddy field of the varying degree of absorptivity of the soil surface is calculated and is shown in fig. 2. For example, the absorptivity of paddy field is 42% and 93% respectively, if the stagnant water is 5cm deep, and absorptivity of soil surface is 0% and 100% respectively.
Some experiments were also made on a model field bearing on the same problem, in which the soil surface of each field was covered with various metal planes 0.1mm thick having different absorptivity. Of caurse, the maximum temperature of water rises monotonously with the increase of absorptivity of paddy field (fig. 3).
The maximum temperature of water in the paddy filed of absorptivity 0% is lower than the maximum air teperature as the rise of water temperature is due entirely to the heat transfer from air. But the direct effect of solar radiation causes the temperature difference between air and water on the field having absorptivity 93% (soil absorptivity 100%) in the field covered with shallow water, if the air temperature is nearly equal to water temperature. In the above experiment, as the temperature difference was about 5 the temperature difference per 10% of absorptivity of paddy field was only about 0.5°C. Therefore the difference of water temperature in every individual field is not considerablly great because the absorptivity of real field is more than 85%.
Nocturnal cooling of water did not differ from each other by the different absorptivity of soil surface, and the held of the highest temperature in daytime had the highest temperature in the early morning as well.

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1. This study was made in order to find out the relations between wind erosion and the width of furrows.
2. It was found that the wider the furrows became the higher its crest rose. But no definite ratio of the width of the furrow. to the wave height, was found.
3. As to the relation between the width of the furrow deviled by the wheat height and the wave crest height devided by the width of the furrow, the latter increases as the former increases. When the former becomes 12 to 15, however, the latter increases more. This is perhaps because at the furrow in the wheat field where the width is around 12 times the wheat height, the wind velocity rises above the velocity within the limit of which the wind does not blow off earth soil owing to the decrease in the effect of protection against the wind.
4. The inclination angle of the sand ripple in the wheat fleld is quite contrary to that on a sand dune; it is acute at the windward and obtuse at the leeward.
And in the process that the sand ripple is formed in the furrow in the wheat field, the most of the cultivated sand grains smaller than 0.1mm in diameter are lost, while pebbles and coarse sand are left accumulated, changing cultivated lands sand fields.

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This paper deals with the heat balance of the surface of a body, on which dew condenses.
Let Q_r (cal/cm² sec) be the heat loss of the body by radiation, Q_e by conduction, w(g/cm² sec) the rate of condensation of dew, and L the latent heat of vaporization. Then the equation (2) holds true, in which Q^r was determined by Brunt's formula as shown by equation (3) and (4). Q_c and W was determined by the formula of M. ten Bosch in the case of natural convection, and by Brasius formula in the case of laminar flow of air, applying the law of similarity.
So we can obtain formulas (7) (8) (9) and (10). The equation obtained putting for these in to the
(2) above was solced graphically with help of Fig. 1 and 2 and the temperature difference of air from the plane surface was obtained.
Namely we can get the surface temperature and the amount of dew on a body, using the observed values of air temperature, vapor pressure and wind force.
The calculated values well agree with the observed ones.

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At present, the frame paper which obstructs extremely the heat transfer with the air exchange and the evaporation from the surface is being used for the temperature rising in the seedling beds.
The transparency of the frame paper has been frequently studied by many researchers, but the relations between temperature in the seedling bed and physical properties, especially the aeration of the frame paper have not been studied.
In this report, then, authors experimentally deals the aeration of the frame paper and its effect on the temperature in the seedling bed of rice, and the experiments were carried on the three points, i.e. the measurement of the aeration of the frame paper, its effect on the heat transfer coefficient, and that on the heat balance in the paper frame.
The aeration of the frame paper was measured by means of so-called the sucker-method described in Fig. 1. The relation between the pressure-difference at the both side of paper and the aerated amount through the paper is shown in Fig. 2, in which the curve (a) and (b) show that of the original paper and oiled paper, respectively. This result shows that the aeration of the frame paper is decreased by the oiling.
If we assume that the frame paper is a kind of porous materials which is made from the cellulose, and that the pore in the frame paper is the capillary tube, then the forces acting to the air in the capillary tube are regarded the pressure-difference and the frictional stress, and those relation is shown in Eq. (2. 1). Eq. (2. 2) derived from Eq, (2. 1) indicates the critical pressure-difference enough to aerate through the each size of the capillary tubes. Provided that the external force can be neglected and the mean flow speed of the air in the capillary tubes is 0.5cm/sec., the calculated values are shown in Table. 1.
After Fukumoto's paper, we can assume that the average diameter of capillary tubes in the frame paper is smaller than 20μ and that no larger pressure-difference than 10mmH₂O between in and out of the frame will occur under ordinary weather condition, then it may be inferred that the air flow through the paper is very little.
We carried out following two experiments in respect to the effect of the aeration on the heat transport from the ground surface, and for them, some sheets pf a specific paper given various aeration by means of varying the number of the artificial pinhole per unit area (Table. 2) were prepared.
At first, by using the apparatus as showed in Fig. 1b, how the heat-transfer coefficient at the heated surface varies on account of covering with the divers aeration paper was measured, The results are represented in Fig. 3.
Another experiment was done on the pattern of rice seedling-bed at outdoor. Above mentioned papers were spread on the soil tanks (60×60×30cm) filled up with water 5cm. in depth. During 13 days the temperatures at three places, middle of the water, soil surface in the bottom, and the air layer adjacent to the water surface, were measured by the thermo-junction, and the effect of aerating resistance (pressure-difference required to aerate the air 0.1cc/cm. sec.) on the virtual eddy diffusivity in the air layer adjacent to the water surface and on the heat balance in the pattern of seedling bed was calculated. Those results are shown in Fig. 4. in together with the each aerating resistances and the each relative amplitudes of the water temperature change. The eddy diffusivity (K) and R (indicate the micrometeorological characteristics) decrease rapidly with increasing of the aerating resistance at the range lower than about 0.04-0.06mm H₂O., but at the higher range those decreaments become very slow and the variances of K and R with the increase of the aerating resistance were almost negligible.
According to the above results, we shad be able to conclude that the aeration of the practical frame papers having the higher value

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The writer mailed every primary school in Nagano Prefecture and Kitakoma Country, Yamanashi Prefecture adjacent to the north of the former in the spring of 1938, in order to ask the observation of the flowering date at the domain of the individual school. The successful reports from as many as 1456 spots were all owing to the observer's cordial cooperations in this work.
Draw the sections of the Valley Kisogawa, Tenryugawa and Chikumagawa and plot the above flowering dates at the corresponding localities in the same maps (Fig. 1, Fig. 2, and Fig. 3)!
1) The examination of Fig. 1 shows that the flowering dates were retarded in proportion to the height above sea level, viz, the flowering date is the linear function of the altitude of the locality where the tree stands.
2) Fig. 2 also affirms the phenomenon of Fig. 1, though the dates are samewhat retarded considering the height at the left end of the flowering date curve, This causes that the area is the place where the southerly strong wind blows through the year and where the Tenryugawa incisedly streams down and the valley stand exceedingly higher than the bottom. Moreover we can judge from the distance between two curves of 1936 and 1938 that the visit of spring in 1938 was approximately ca. 6 days later than that in 1936.
3) Contrary to the former two cases, the flowering date curve of the Chikumagawa AA' is quiet curious. It is indeed natural that the curve runs parallel to the topography of the valley at the upper half course, but what is the cause of such a remarkable retardation at the lower half course?
Now elliminate the latitudiual effect from the original curve AA′ and the curves BB′ and CC′ are given, the former being based on Dr. Daigo's value (Ca 4days/1°N) while the latter on K. Misawa's one (Ca 6.5days/1°N). Even if the latitudiual effect is taken into consideration, there still remains a noteworthy concavity.
In winter, deep snow wrapps up the lower course of the river, whereas the climate of the area south of the former is rather arid. Moreover the Ueda basin lying in the leeward side of the winter winds, the seasonal winds are extremely weak and the air temperature is warmer, As for the former district, the thawing of the heavy snow is late, so that it remains chill to retard the cherry blossom.

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The study of air temperature lapse rate on the mountain slope is of special interest for the local climatological consideration. The data accumulated at the two climatological stations, located at the lower part of the southwestern slope of Mt. Neko, Nagano pref. (Fig. 1), are used for the calculation of the air temperature lapse rate. The alttude of st. A above the sea level is 1395m, st. B is 1280m. Seasonal and annual mean of lapse rate of maximum and minimum temperature are shown in Tab. 1. A particularly important result is an inversion state of minimum temperature in the mean condition. In the case of the annual mean, the higher the altitude on the slope, the warmer the minimum temperature at a rate of 1.13°C/100m. Then, to investigate the frequency and magnitude of lapse rate of maximum and minimum temperature in detail, a statistical method, calculation of probable ellipse, is applied for each season. As is shown in Fig. 2, spring and autumn have a greater major axis as a consequence of increased interdiurnal temperature variabilities in the respective season. The eccentricity, however, of the probable ellipse of maximum and minimum temperature (Tab. 3) change in parallel in spring, summer and autumn on the whole. As the minimum temperature in winter is most characteristic, its eccentricity in winter show the special value. This is because of the strong winter inversion both in frequency (Tab. 4) and magnitude (1.6°C/100m) caused by the effect of snowcover and the longer duration of nighttime.

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常風向は微細なる地形地物の影響を鋭敏に蒙り, いずれの地点の常風向も機械観測のみによつて推定するには現在の施設はあまりにも疎である。ところが柿及び稲の傾曲景はそれぞれ夏季及び秋季の常風向を示し, 葭及びススキの穂の傾きは冬季の風を推定するのに有力なることを知つた。よつて小文ではその一例とし長野県における夏季常風向図を掲げた。特に今回執筆者の求に快く応じすばらしき写真を撮影して下さつた向山雅重氏に衷心の御礼を申上げたい。

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