364 



EXPERIMENT STATION BULLETINS. 



Lenten season, epidemics, and holidays also tend to increase the loads. A 

 brief water epidemic in one city increased the sale of milk 25 per cent for the 

 whole city in a week's time. 



Table No. I 



THIS TABLE SHOWS THE DIFFERENCE IN THE AMOUNT OF MILK SOLD IN WIN- 

 TER ATD SUMMER. 



UNNECESSARY DUPLICATION. 



Upon comparing the actual delivery with the theoretical we find that there 

 is a great difference in the amount of duplication. Some things which affect 

 this have already been mentioned on pages 5 and 6. From the theoretical 

 system we find that it is impossible to formulate a system of delivery in which 

 the entire city is served without some duplication. The duplication which is 

 unavoidable we have considered as necessary duplication. The difference in 

 amount of duplication between the actual and theoretical systems is called 

 unnecessary duplication as shown in the following Table No. II. 



