410 C S. WILLIS. 



of typhoid loses its vitality and dies out when discharged 

 into ordinary sewage, it would appear that this is not the 

 case when sewage finds its way out of a sewer, and perco- 

 lates through the ground. Under these conditions basic 

 nitrates are formed by oxidation of ammonia and nitro- 

 genous matters, which favour the life and growth of the 

 bacillus of typhoid, and enable it to persist for long periods." 



In 1908-9, a small country town in this State forwarded 

 to the Health Department, for analysis, samples of water 

 from ten wells. These waters were analysed in the 

 Department's Chemical Laboratory, with the results shown 

 in the accompanying tables I and II. Eight of these were 

 condemned by me as unfit for drinking purposes, and in 

 seven cases the condemnation was made chiefly, or entirely 

 on the N as nitrates figures, which were 0*480, 0*800, 1*100, 

 1*200, 1*700, 1*700 and 4*300 parts per 100,000 respectively. 



Fresh samples from some of the wells were then sub- 

 mitted by the residents to a private analyst, who, although 

 obtaining similar figures to ours, gave an opinion to the 

 effect that the waters were fit for drinking purposes. 

 There then followed a good deal of local agitation, and I 

 was despatched to the town in question to see the actual 

 state of the wells. The following conditions were found. 

 The town is traversed from north to south by a creek. 

 Much the larger portion of the town is built on the east 

 side of the creek, and here the ground has a distinct slope 

 towards the creek; all the condemned wells were in this 

 portion of the town ; also, there were 18 cesspits situated 

 for the most part on a slightly higher level and directly 

 above the wells. The relative situations of wells and cess- 

 pits will be seen by reference to attached map of the 

 town. The two wells not condemned were found in the 

 west portion of the town where there were no cesspits. 

 The soil at this town is very porous, so much so that 



