1 86 The Soil in Relation to Disease. [part I. 



have been made only in a few isolated localities. We would therefore take the 

 present opportunity of pointing out their value and of pressing on the attention of 

 the Meteorological Department the importance of investigating and recording some 

 of the more prominent features of sub-soil phenomena. 



From an etiological point of view it is obviously quite insufficient to be informed 

 merely of atmospheric meteorology and to remain in total ignorance of telluric 

 conditions. This view of the case is becoming more and more realized in Europe, 

 and the value and importance of acquiring the necessary data in this country cannot 

 be over-estimated. 



We have thought it better to confine our attention to the consideration of the 

 phenomena presented by a period during which our observations on soil-conditions 

 were most numerous and of the most varied nature, but data regarding water-level 

 and soil-temperature for a considerably longer period are given in the accompanying 

 tables. 



The period specially considered ranges from the month of July 1873 to August 

 1874, and for this period full details are given regarding the temperature and carbonic 

 acid-contents of the soil at 3 and 6 feet from the surface. The coincident phenomena 

 of rain-fall, atmospheric temperature, and velocity of wind are also given, together 

 with the statistics of total mortality ; of mortality from cholera ; and of the prevalence 

 of fever and dysentery. 



Figures regarding all these phenomena will be found in the tables (I — VI), and 

 the relations which they bear to one another are, moreover, graphically represented 

 in a series of diagrams of graduated curves. An additional chart has also been 

 constructed showing the monthly fluctuation in the carbonic acid of the soil- air 

 as compared with the results of the experiments conducted in Munich by von 

 Pettenkofer. 



(1.)— Mode in which the Observations have been conducted and the sources of the 

 various Data. Description of apparatus employed to obtain the air from the soil. 



It will be convenient, before proceeding to describe the results of the observations, 

 to give a brief account of the sources from which the data were derived and the 

 means by which they were obtained. 



(a) — Carbonic Acid of tfte Soil- Air. 



The data on this point were obtained by our own observations. During a 

 considerable portion of the period under review the experiments were made with 

 regard to one locality only, but subsequently another series was undertaken so as 

 to ascertain the amount of carbonic acid in two localities separated from each other 

 by about 50 yards. 



The depths selected for observations were in both cases 3 and 6 feet respectively -, 



