PART II.] Chemical Analysis of the Water at Delhi. 417 



As analyses made in an extemporised laboratory can seldom be so satisfactorily 

 performed as when conducted with all the proper appliances, and as we were anxious 

 that our estimates should be comparable with those of a professional chemist, we consulted 

 Professor C. H. Wood, the Chemical Examiner to the Grovernment, who very kindly 

 undertook the analyses of these particular samples himself, and has favoured us with 

 the following tabular statement of the result : 



Mr. Wood writes : "All the waters, in addition to lime, contain notable quantities 

 of magnesia. The alkaline metal present is chiefly sodium, the proportion of potassium 

 being very small. The most noticeable feature of these waters is the large proportion 

 of nitrates present." 



On comparing the figures given in Table XIII, with those given regarding the 

 hardness and chlorides in Table XII, it will be found that they both indicate excessive 

 hardness as a prominent feature in Delhi waters, as well after as before the rains. 



How far an excess of certain salts in a water may produce the Oriental sore is a 

 question demanding further inquiry. What we do know at present is (1) that it is 

 something connected with the water of the wells in Delhi which appears to determine 

 the occurrence of the disease there ; (2) that this water is characterised by its excessive 

 hardness, and (3) by the presence in it of very large quantities of salts. It does not 

 necessarily follow that the hardness and saline quality of the water should be the direct 

 cause of the disease ; they may be accompanied by some special compound which is 

 the real efficient agent, but there certainly are some points which seem to indicate that 

 the hardness of the water may be taken as an index, at all events, of its containing 

 deleterious ingredients conducive to the development of cutaneous affections of the 

 character of Oriental sores. 



Taking the well-known fact of the absence of these sores among the population 

 of Bengal Proper, and the figures relative to the occurrence of " abscess and ulcer," 

 among the native troops in the same region, and comparing these with the prevalence 

 of such forms of the disease in other parts of the country, the general fact comes out 

 very clearly, that where the water is soft, such diseases are at a minimum, and that 

 where it is hard, they increase in prevalence and attain a maximum in a place, such 

 as Delhi, where the hardness of the water is excessive.* 



It would be a matter of great interest to carry the analysis of this question out 

 in detail, and to determine the question for individual towns and stations. This, 

 however, cannot be done at present; for, on the one hand, there is a want of definite 

 statistical information regarding the occurrence of the disease, and on the other 

 there are no chemical data of assured accuracy regarding the condition of the 

 water. 



* It is at present impossible to proceed beyond a consideration of the more general phenomena of the 

 distribution of the sources of the disease, as our information on the subject is of so imperfect and fallacious 

 a nature. For example, in the table regarding European troops, Dum-Dum and Fort William occupy 

 a very high place as stations subject to abscess and ulcer, while, as a fact, forms of diseases akin to Oriental 

 sore are practically unknown there. 



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