A blood pressure survey was made on 2, 022 workers of a big electricity plant residing in the same district and exposed to similar environments. Factors taken as contributing to the causation of hypertension were: Age, hereditary disposition, personal clinical history, body type, Rohrer's index, thickness of the pinched skin, specific gravity of the blood, body weight change, caloric intake, quality of food, alcoholic intake, smoking, hours of sleep, hours of transport, number of family member, kinds of work, and intensity of labor. The workers were divided in two groups, i.e., those above and below 40 years of age. The former was again divided in those with hereditary predisposition and without it, to see whether or not the same a priori factors affecting these both groups have different bearing on the causation of hypertension. The results are as follows. 1. Irrespective of age, significant contribution to hypertension were found in body type, state of nutrition, alcoholic intake, smoking, and hours of sleep. 2. Irrespective of hereditary predisposition, significant contributions to hypertension were found in body type, state of nutrition, and hours of sleep. 3) With concomitance of age or hereditary disponsition; food, hours of transportation, number of family members, and labor conditions are contributory to hypertension. Obesity was found to be the most significant contributory factor. Even without any hereditary predisposition, obese workers over 40 years of age showed hypretension in about 50%. This and the above stated facts may be useful for supervision of workers as to prevention of hypertension.

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The Japanese "Kana" typewrite is going to be widely used in offices. But the arrangement of letters and numbers on the keyboard is not standardized among various manufactures. A study was made to determine the ideal arragement in the keyboard for maximum efficiency in man-machine system. On the side of machine, sizes of various keyboards, loads for each row as conferred by hands, and fingers were measured. And on the side of man, the physiological capacities of fingers were analyzed. Working area of fingers or motion of upper extramities related to typwriting, anatomical position of the finger phalanges, electromyogramm, tapping rate and compound reaction time were observed on skilled and unskilled typists. It is suggested from the analysis of the data secured in these investigations that keys of the "Kana" typewriter are not so arranged that the load of each finger is fitted to the physiological capabilities of the finger.

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Medical examinations of the workers exposed to carbon disulfide in a cellophane factory were made, and the results obtained were analysed. The examinations consist of hematological examinations (erythrocyte count, hemoglobin content, reticulocyte count and the ratio of neutrophilic leucocyte count to lymphocyte count-N/L), liver function tests (urobilinogen in urine, Millon's reaction of urine, Takata's reaction of serum, cephaline cholesterol test of serm and the ratio of albumin to globilin in serum-A/G), measurements of blood pressure (upper arm and eye), ophthalmologic examinations (examinations of visual field and retina), adrenocortical function tests (17-OHCS and 17-KS in urine) and other examination (total glucuronic acid, glucuronic acid of glucoside type and creatinine in urine). The results obtained are as follows: 1) The group exposed to carbon disulfide showed higher abnormal findings in almost all items of examinations than the control group of unexposed workers, and there were significant differences between the two groups on the following symptoms, namely fall in N/L in blood picture, narrowing of the visual fields (especially colour visual field), increase of urobilinogen in urine, fall in A/G of serunm, decrease of 17-OHCS and 17-KS in urine, decrease of glucuron acid and glucuronic acid of glucoside type in urine and increase of creatinine in urine. Besides, anemia, increase of reticulocyte count, some findings in retina and rise of blood pressure were found in low grade. 2) Coeffcients of correlation between two of the following symptoms specially noticed in this examination were calculated; N/L in blood picture, liver function, blood presssure, visual field, retina findings adrenocortical function and creatinine in urine. And, there were statistically significant correlations at 1% level between two of the following three symptoms, impairment of adrencortical function, impairment of liver function, and fall in N/L in blood picture; also between impairment of adrenocortical function and constriction of the visual fields. But there were nocorrelations in other combinations of the above symptoms. These results shows that in mildcarbon disulfide poisoning symptoms appearing in each worker are considerablly varied. Therefore, for early detection of carbon disulfide poisoning, it is to be desired that many kinds of examinations as mentioned above are taken. 3) The group exposed to carbon disulfid showed wider standard deviations in values obtained in almost all examinations than the control group. This is due to the fact that in the group exposed to carbon disulfide there are some poisoned people mixed in healthy men, and it seems that this is not specific and found not only in workers exposed to carbon disulfide, but non-specific and generally found in workers exposed to some kind of poisons. Some workers of the group exposed to carbon disulfide showed rather higher level of adrenocortical function than the control group. Thus, the carbon disulfide is supposed to act as a kind of stressor causing elevated adrenocortical function.

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