THE METER RATE SHEET 27 



of diagrams may be resorted to, but is is more convenient to 

 make use of logarithmic paper. 



By selecting convenient logarithmic scales, practically the 

 whole range of rates in the water works business can be repre- 

 sented on one small sheet of paper. Such a blank sheet for 

 plotting rates was prepared by a committee of the New England 

 Water Works Association. Its size is n by 8| inches and the 

 scales and ranges were selected to conveniently and adequately 

 represent the ordinary range of the water-works business. These 

 sheets have been printed for separate distribution, and are 

 available in quantities for meter rate studies. The figures 

 used in this volume to show meter rates are based on this sheet, 

 reduced in size and with fewer lines so as to avoid crowding. 



On this sheet the vertical scale shows the average rates per 

 1000 gallons. The principal horizontal scale shows the quanti- 

 ties in thousands of gallons per annum, but there is an auxiliary 

 scale which shows the quantities in gallons per day. This is 

 useful in giving a clear idea of the quantities. 



The diagram is divided into three parts by two vertical lines 

 heavier than the others. The position of these two lines were 

 chosen more or less arbitrarily by the committee to classify 

 the consumers according to the quantities of water drawn by 

 each. These three divisions are called for convenience Domestic, 

 Intermediate and Manufacturing. 



Domestic consumers are all those using less than 820 gallons 

 per day, or 10,000 cubic feet per quarter; manufacturing con- 

 sumers are those taking over 8200 gallons per day, or 100,000 

 cubic feet per quarter. The intermediate consumers are those 

 that fall between. The names have no significance beyond 

 defining the quantities of water which they represent. 



By always using the same sheet, the position of the line upon 

 it comes to have a definite meaning to one who is making a 

 number of such plottings, and comparison between different 

 rate schedules may be rapidly and accurately made. The sheets 

 being printed on mbderately thin paper, it is possible to make 

 blue prints from them and also to trace a line from one sheet to 

 another, so that a tracing may be made showing the plotting of a 



