62 THE AMERICAN MONTHLY [March, 



The use of sand as a filtering medium for this purpose was suggested 

 by Desmond FitzGerald, Boston Water Works, but it was to the in- 

 genuity of Prof. Sedgwick that we owe the working out of the really 

 useful application of those various devices. My own subsequent im- 

 provements are in the nature of refinements of technique. 



The practical value of a method of this character will be readily 

 recognized by all who understand the limitations of chemical analysis 

 as applied to the decision of questions relating to the sanitary value of 

 potable water. The most useful of the various chemical methods 

 recognizes only two classes of organic impurity, . namely, free and 

 albuminoid ammonia, and groups every organic substance occurring in 

 water as one or the other of these. This has resulted in the condemn- 

 ing of the water of mountain streams by chemists who ventured positive 

 opinions.as to sanitary value on the evidence of chemical analysis alone. 

 The use of the biological method, by exhibiting clearly the character 

 of the organic contamination, will, therefore, lead to a more accurate 

 knowledge of potable waters than can be gained by chemical analysis. 



Morever, as we gain more knowledge of the real sanitary significance 

 of the variolas forms of plant and animal life, the daily or weekly fluc- 

 tuations in quality of a public water supply can be quickly obtained by 

 the use of this method of biological analysis, and it is probable that 

 in the very near future all public water supplies in this and adjoining 

 States will be regularly subiect to such examinations. Indeed, the State 

 Boards of Health of the States of Massachusetts and Connecticut have 

 already begun a series of examinations, either weekly or monthly, in 

 their respective States, and in the city of Boston I have been engaged a 

 portion of my time for the last eight months in supervising the details 

 of beginning an elaborate study of this kind as applied to the Boston 

 supply. The Boston Water Board, with liberal foresight, have recog- 

 nized the value of such new methods of examination, and have pro- 

 vided liberally for a practical test extending over a number of years. 

 Daily I'ecords have been made for the last six months and show results 

 of great value, though the full value of such work can hardly be de- 

 termined in so short a time. At a recent meeting of the New England 

 Water-Works Association, Mr. F. F. Forbes, vSuperintendent of the 

 Brookline, Massachusetts, Water Works, has given an interesting 

 account of some similar studies which he made during the last season, 

 with his results, and I will refer those interested to the Journal of that 

 Association for further detail of such work. 



[Mr. Rafter then adds some tables showing results of the use of his 

 apparatus and a blank form for recording results. — Editor.] 



Figs in California. — The fig tree which belongs mainly to the 

 shores of the Mediterranean has been introduced into California. 

 There are now 50 varieties under experimental cultivation, with the 

 view to selecting the few best adapted to the coast. It is believed that 

 by judicious selection of location and varieties fig culture will become 

 a success in California. 



