In the previous report, the author has presented his finding which indicated the general trend of the improvement in physical growth among primary and middle school children in Sendai in post-war days, and discussed whether this acceleration of growth is general or is limited to a part in these groups.
In the present study, similar investigation was undertaken with primary, middle and highschool children in Miyagi Prefecture and in many other parts of Japan.
The results showed that the growth in body length in the young population may be said to beimproved in a general way in the recent years, but the growth of body weight and chest girth have not been so expedited generally, remaining as low as ever in the subjects with low grade of development.
Such an acceleration of physical growth in the different ages, when viewed in the light of total age of growth, seems to present a picture of general precocity.

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In order to investigate the genesis of the poison in the fish and shellfish from Minamata Bay biological and chemical properties were compared with mercury compounds experimentally accumulated in the control shellfish.
1) The mercury content in the shellfish Hormomya mutabilis (Gould) showed ca 100 ppm of dry weight at the end of 1959, but afterwards it decreased gradually and showed 30 ppm in August of 1960, probably on account of the completion of the waste treatment equipment of Minamata Factory. But in January of 1961, it increased again and showed 50 ppm, perhaps owing to the transitory suspension of the operation of the waste treatment.
2) Toxicity of mercury compounds to the short necked clam-Venus japonica (Deshayes) was observed. Venus could survive for about 1 week in the sea water containing mercury compounds at the rate of 0.3 ppm as Hg, and the mercury content in Venus showed ca 40-50 ppm of dry weight. Na₂S₂O₃ suppressed the toxicity of mercury compounds, but Ca-EDTA had no effect on it. The mercury content in Venus depended generally on the surviving period and not on the toxicity, but the accumulation of mercury in Venus cultured in the sea water containing alkyl mercury compounds had a tendency to be greater than that of other mercury compounds.
3) The mercury content in organs of the shellfish from Minamata Bay was higher in the nervous nodules than in other organs. But the mercury content in organs of the shellfish cultured in the sea water containing HgCl₂ was higher in the gills than in other organs.
4) The shellfish Venus cultured in the sea water containing HgCl₂ was administered to rats and mice. The distribution of mercury in organs of these animals had the higher content in the kidney and the liver.
5) The shellfish cultured in the sea water containing inorganic and organic mercury compounds were digested with pepsin at pH 1.6 and the digests were distilled with steam and the mercury in the digested fluids and that transferred into distillates were observed. Mercury was found in digested fluids and distillates of the shellfish which was accumulated with alkyl mercury compounds, especially with methyl mercury and ethyl mercury, but not with other organic and inorganic mercury compounds.
6) These results suggest that organic mercury compound accumulated in the shellfish has come directly from the sea water, and has not been synthesized from inorganic mercury compounds in the shellfish. And from results of the digestion and the steam distillation of the control shellfish cultured in the sea water containing many inorganic and organic mercury compounds, the organic mercury in the shellfish from Minamata Bay was supposed to be an alkylmercury compound, probably methyl or ethyl mercury compound.

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1) Some organic mercury compounds which are soluble in organic solvents were included in the waste from the acetic acid production plant of Minamata Factry. But these organic mercury compounds had no relation to Minamata disease.
2) Among organic mercury compounds which are considered to be produced in the process of the production of vinylchloride, ClHC: CHHgCl and (HgCl)₃CCHO were considered to have no relation to Minamata disease. But some intermediate product from these organic mercury compounds was very toxic to animals.
3) In muds of the drainage from Minamata Factory, an organic mercury compound was proved. And the chemical property of it resembled to that of the mercury compound extracted from the fish and shellfish from Minamata Bay.

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The present studies were made on the influence of thermal stress upon excretion of urinary glucuronic acid in male albino rabbits, weighing 2.5 to 4.6 kg. The animals were divided into two groups. One group was used for the experiment on seasonal variation. The other group was remained in chamber, where temperature could be controlled artificially, in order to study the responses by exposure to heat and cold.
Analyses of urinary glucuronic acid and ether glucuronide (OG) were carried out by the naphtoresorcin picrate method. The concentration of urinary glucuronic acid was expressed as G/C ratio in urine. Principal results were as follows.
1) G/C ratio in urine decreased markedly during the period from July to September. It was, on the contrary, found to increase during mid-winter, from December to February. There was a significant (P<0.05) inverse relationship between environmental temperature and G/C ratio in urine.
2) The fluctuation of OG/G ratio in urine could not be observed through the year. Namely, it seemed to be kept at the normal range even in summer.
3) After exposure to cold stress (about 10°C) for three days in summer, G/C ratio in urine increased rapidly and returned to the range of pre-experimental levels after cessation of exposure.
4) After exposure to heat stress (about 30°C) for three days in winter, G/C ratio in urine decreased and returned to the winter values after cassation of exposure.

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Methods engineering combined with motion and time study seems to play an important role for finding the economical way of performing the operation, standardizing the operation, and determining the time standard in industry. Motion time engineers sometime believe that the design or analysis of various industrial machines or tools should be determined by the application of methods engineering. However, they only concentrate their attention on the time factor in relation of man to machine, and not on the ratio of input to output of man-machine relationship.
So far as man-machine system, a minimal work unit, is concerned, the design of equipment should be evaluated not only in speed but in other ways, accuracy, comfort, safety and muscular force, so that the operator of such equipment will not be stressed beyond his physiological and psychological capabilities.

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