| Summary: | The connection between certain conditions of soil and the incidence of some infectious diseases has long been recognised by Physicians but the way in which these conditions operate has been variously explained. This paper shows a correspondence between the maximum of carbonic acid and the maximum reading of the earth thermometer at three feet. Late summer, when the temperature of the soil at three feet rose to the maximum,showed also the greatest amount of carbonic acid. Throughout the entire year much rain always produced a marked temporary increase in the amount of carbonic acid. These facts probably find their explanation in the increased bacterial life called into renewed activity by the heat and moisture. Moisture, as after much rain, may also act by mechanically sealing up the pores of the soil and thus preventing the normal escape of carbonic acid into the general atmosphere. The highest reading of the earth thermometer was towards the end of August when it ranged in the neighbourhood of 56° Fahr. Edinburgh is not what is known as a "Diarrhoea Town" that is, one in which that disease plays havoc with the infantile population in late summer and early autumn, but still, it is observed that most cases of infantile diarrhoea do occur at the time corresponding with the maximum reading of the earth thermometer at three feet, as is shown by reference to the Report of the Medical Officer of Health, Edinburgh 1898. The diurnal variation in the amount of carbonic acid showed an evening excess over the morning as the year approached near to the summer solstice and beyond it to the maximum reading of the year which occurred in the last days of August. After this period a morning excess over the evening was observed as the year approached near to the winter solstice and beyond it to the minimum reading of the year which took place in the end of March. During March, April and May, and again in September, October and November, the morning and evening variations were but little marked and temporary conditions of ...
|
|---|