THE SLIDING SCALE 15 



another limit and another price, and so on. In some cases two 

 prices only are used; in others three, four or more, up to a dozen 

 or twenty, and in fact divisions may be so numerous that the 

 scale practically becomes a table which gives the water rate for 

 every quantity of water that a meter records. 



The jump scale as ordinarily used with a limited number of 

 divisions is open to the defect that anyone can get a lower bill 

 at certain points by drawing an additional quantity of water, 

 that quantity being sufficient to take him into the next lower 

 classification. In other words, by drawing more water, the price 

 per unit is reduced to a greater extent than the increase in the 

 volume. (Example: Harrisburg, p. 46.) 



Modified Jump Scale. Under this arrangement each step 

 in the jump scale is subdivided into two parts, the second of 

 which comprises all those quantities for which it would be 

 possible to get a lower rate by drawing more water. For these 

 quantities a lump sum collection is made, which sum is the mini- 

 mum that could be obtained under the next step. For the first 

 part of each step the rate remains as with the jump schedule. 



This type of schedule has been officially used in only a small 

 number of systems. (Examples: Syracuse, Winnipeg, pp. 54 and 

 56.) Practically it has found much wider application, because in 

 works where the jump scale is used the practice has grown up of 

 giving customers the advantage of any theoretical saving that 

 might be made, on the supposition that they had actually in- 

 creased their drafts to the point of bringing them into the next 

 lower division. 



Common Sliding Scale. Under this arrangement the water 

 first drawn up to a certain limit is charged at a certain rate. 

 Additional quantities are charged at a lower rate, but the higher 

 charge on the first quantity remains as part of the bill in all cases. 

 This is the best type of sliding scale in common uses. (Example: 

 Atlanta, p. 36.) 



Schedules under this form may be further subdivided as to the 

 number of classes or rates that are provided. Schedules with only 

 two rates have been used by the Wisconsin Railroad Commission 

 and occasionally elsewhere. (Example: Madison, p. 50.) 



