340 Proceedings of the Royal Physical Society. 



into the nearest stream, if, indeed, they are not washed in the 

 stream itself ; the excreta from the fever patient is, by his 

 kind attendants, hurriedly popped into the burn, in order that 

 it may be away from themselves ; while all the time the next 

 man down the stream is drinking this lively beverage, or it 

 may be he is bulking with it the milk which he supplies to 

 some neighbouring city, and thus is pouring into our midst 

 what may be the seeds of an epidemic that may hurl pre- 

 maturely into eternity hundreds of his fellow-beings. 



'' For the best method of dealing with such cases as these, 

 it is only necessary to refer to the very clear ' instructions ' 

 drawn up by Dr Littlejohn, medical officer of health for 

 Edinburgh, and it would be well for all concerned if these 

 or other equally efficacious means of dealing with fever 

 patients — were made compulsory throughout the country. 

 Like the work of most other public benefactors, these ' in- 

 structions ' of Dr Littlejohn's were branded as ' useless,' 

 ' absurd,' ' unworkable,' etc. ; but notwithstanding that, there 

 is every evidence already that they were perfectly necessary, 

 and it is not saying more than is true when we make the 

 statement, that, but for the foresight of the Edinburgh medical 

 officer of health, that city would in all probability be now 

 the centre of a typhoid epidemic. . . ," 



Much more could be said in regard to burn and river 

 pollution, but for the present perhaps there is sufficient. 



The next sources of water supply to which I would refer 

 are springs so-called, and wells. 



What are these springs ? For the most part they are 

 simply water finding its way from a higher to a lower level, 

 licking up in its travels all kinds of decomposing or decom- 

 posable animal and vegetable matter ; and just in proportion 

 to the distance it runs, and the impurities it meets with in 

 its course, will be the extent of pollution. No doubt these 

 spring waters pass through considerable depths of soil, which 

 it may be claimed will act as a filter, and purify the water. 

 No doubt it does so, in so far as removing insoluble or 

 suspended matter is concerned, but it must be remembered 

 that by far the most dangerous impurities are those which 

 are in solution, and these are but little likely to be affected 



