17 



the vessel in which the water is heated : hence the '• furrinp; " of 

 our boilers and kettles. 



When ordinary soda soap is added to tlie water it forms an 

 insoluble lime soap by its action upon the acid carbonate of lime, 

 and it is owing to the production of this insoluble soap within the 

 pores of the skin that washing in the Kent water is so difficult 

 and unpleasant an operation. 



In practice the water is rendered less hard, or " softened," 

 either by boiling, or by the addition of " washing soda," which 

 also causes the conversion of the acid carbonate in the water into 

 the ordinary carbonate. On tlie large scale, hard water such as 

 ours is successfully softened (at the Colne Valley Works, near 

 Harrow, and at Canterbury, for example) by adding lime water, 

 whereby again the acid carbonate is converted into the ordinary 

 carbonate, which falls out as a crystalline deposit. 



Tlie amount of personal inconvenience resulting from the use 

 of so hard a water in our district is undoubtedly very great. Soap 

 and soda are used to waste in very large quantities in order to 

 overcome the evil. Probably also if statistics could be obtained 

 as to the life of our kitchen kettles and boHers, in comparison 

 with a district in which soft water is used, the result would be 

 startling, and would clearly show how costly an article we are 

 provided with. 



Reference was made to the ease with which rain-water might 

 be collected in a fairly clean state by fitting an interceptor between 

 the store tank and the delivery pijie. 



The Lecturer said, with regard to filtration, that it was an insult 

 to the Kent water to filter it through any of the ordinary filters, 

 which were more likely to do harm than good, owing to the ex- 

 treme difficulty of getting domestic servants to keep such filters 

 clean ; moreover that nothing was to be gained by filtering Kent 

 water, provided it had been taken direct from the main, or from 

 a clean tank. A filter was shown and explained, consisting of a 

 series of paper discs through which the water was forced, the paper 

 of these discs having incorporated with it a quantity of purified 

 animal charcoal ; the filter was so constructed that new discs could 

 be put in with the greatest possible readiness at any time. 



