CHEMICAL AND BACTERIOLOGICAL EXAMINATION OF SOIL. 763 



From this it would appear that the addition of organic matter has a well-marked 

 influence in increasing the number of bacteria in soil, but that there is any definite 

 relation between the amount of organic matter and the number of organisms present is 

 not apparent in my results. 



For example : — Comparing the number of organisms present in sample 11 with that 

 found in sample 20, we find that they vary very widely although the organic nitrogen 

 and carbon present vary but slightly, the two samples being taken at the same depth, 

 though in different ground. 



Eeimeks, in his research on the soil of graveyards [Zeitschrift fur Hygiene, Band 

 vii., 1889] found that the number of micro-organisms was not greatest immediately 

 under the coffin, as one would naturally suppose, but at some little distance above, 

 although the number in the vicinity of the coffin was comparatively great. 



In one case he found the numbers to be as follows : — 



In the superficial layers, ........ 320,100 \ 



At 1"2 metre, near the coffin, ....... 844,500 J- per c.c. 



At 1*6 metre, just under the coffin, ...... 142,300 j 



In another case he found them to number : — 



At 1 metre, near the coffin, ....... 460,100 ) 



At 16 metre, just under the coffin, 170,300 J per Cc ' 



A further fact developed by Eeimers is that the number of bacteria diminishes 

 greatly in the soil beneath the layer containing the coffin. 



Example L: — 



At 1 metre, near the coffin 460,000 \ 



At 1*6 metre, just under the coffin, ...... 170,000 > per c.c. 



At 2 metres, " 56,000 J 



Example II.: — 



No coffin found, but at a depth of 1*5 metre many bones. 



At 1 metre, 985,000) 



At 1-8 metre, 244,600 j- per c.c. 



At 2 metres, 15,600 ) 



In this country exhumations are by no means common, and it is with great difficulty 

 that one can obtain samples of soil from the immediate vicinity of coffins. On only two 

 occasions was I able to obtain such samples, the results of which I state below. These 

 bear out very well, I consider, the statements of Eeimees. 



No. I. :— 



«. Grange Cemetery. Sample taken from immediately under a coffin buried three 

 and a half years previously. Sample taken 6 feet 6 inches from surface. 



|3. Sample taken at a depth of 4 feet 6 inches from surface in same grave as last. 



