PART I.] Microscopical Examination of the Soil. 47 



Six of the specimens were subjected to chemical examination with the view of 

 ascertaining whether the soil near the barracks, at or about three feet from the 

 surface, contained an unusual amount of organic matter or not. One ounce of soil 

 was taken and allowed to stand for twelve hours in pure water, shaking it a few times 

 during this interval ; it was then filtered, and the clear solution examined in the 

 manner usually adopted for the examination of water. 



The results were pretty much the same in all cases ; except in those where the soil had 

 been a " made " one, the amount of lime-salts varied, but I was surprised to find that the 

 soluble organic matter, as estimated by a standard solution of 'permanganate of potash, 

 did not much exceed the amount present in the ordinary drinking water of Calcutta when 

 estimated by the same solution. (The exact relative amount of organic matter present 

 may be ascertained by reference to the foregoing table.) 



From these observations, therefore, I infer that in the ground beneath and about the 

 barracks at Allahabad, both in the old and new cantonments, the amount of oxidisable 

 matter was not in excess, at a comparatively short distance from the surface, at the time 

 when cholera visited that station ; consequently the epidemic could not have been owing 

 to putrefying matter in the soil of the cantonments, unless such matter had been washed 

 into the wells by the rain, and thus infected nearly a hundred and fifty persons belonging 

 to the European troops stationed there. To have produced this, the amount of surface 

 pollution present before the rains set in must, I should imagine, have been very 

 extensive indeed. 



It was also thought desirable that a few samples of the earth should be taken 

 and moistened with water in order to ascertain whether any special form of life, animal 

 or vegetable, would make its appearance. I select two examples. A small portion of 

 dry earth from the new cantonment was placed in a test tube, to which a little water was 

 added, sufficient to cover it. During the first and second days no particular forms of 

 life were observed, but on the third and succeeding days several minute infusoria had 

 become revived, and presented exceedingly active movements (Plate XXII, Fig. xc). 



A similar portion of soil from the Clydesdale Lines was treated in the same way. 



In it also no particular objects were manifest for the first two or three days, but 

 towards the end of a week, in addition to the objects delineated in the last figure, 

 bodies in the circular, still, and active condition — not in any way distinguishable from 

 the animalculge already described as occurring in choleraic and other discharges — were 

 seen to have developed in great numbers, some freely moving in the fluid, and others 

 imbedded in granular matter (Fig. xci). Nothing further was observed in any of the 

 samples, nor could I detect any evidence of the existence of the ultimate elements 

 of fungi. 



I also accompanied the Sanitary Commissioner to the " cholera-camps " occupied 

 by the 58th Regiment, about fifty miles from Allahabad, on the Jubbulpore road ; 

 and Dr. Chalmers, the Deputy Inspector General of Hospitals, very kindly under- 

 took to show me nearly every part of the city and cantonment. To Dr. Irving also 



