Hartley — On the Composition of Tico Hard-Water Deposits. 47 



One great advantage gained by Clark's process when applied 

 to a hard water is not only the softening of the water, but its 

 very thorough purification from dissolved and suspended organic 

 matter. 



Twenty years ago I advised the adoption of Clark's process, 

 under the following circumstances : — 



There were two sources of water — one a stream of fairly soft, but 

 brownish peaty water, unfit for the final washing of fine linens ; 

 the other a spring of perfectly clear and colourless, but very hard 

 water, the quantity of which was insufficient. My advice was to 

 mix the two waters in the reservoir, and to add the necessary 

 quantity of lime-water in the usual manner in order to complete 

 the softening process, whereby the whole of the peaty colouring 

 matter would be precipitated with the lime. I demonstrated the 

 proportions which could be used, and the perfect purity of the 

 water obtainable, but I believe this advice was not acted upon. 



The analysis of these deposits shows forcibly the large pro- 

 portion of organic matter which can be removed by the simple 

 deposition of carbonate of lime. 



The following figures are instructive : — 



The average temporary hardness of the canal water is 12 parts 

 per 100,000 of water. 



Weight of sample of deposit formed therefrom, 1 lb. 10 oz. 



Cubic inches of deposit, 25"26, 



Smallest volume of the water from which this deposit could have 

 been formed, 1354 gallons. 



Volume of the water which can form a cubic inch of such 

 deposit, 53*6 gallons. 



Organic matter in one cubic inch of this deposit, 54 grains. 



Therefore, one grain of organic matter can be removed from 

 the water without softening by means of lime, and the quantity 

 removed may easily be doubled by using the proper proportion of 

 lime-water. 



There can be no doubt that the canal water, by the application 

 of Clarke's simple process, might be made fit for any purpose. 



