498 



WATER SUPPLY AND SEWAGE DISPOSAL 



indicates a reading of 80,000 cu. ft.; the third pointer 8,000; 

 the fourth pointer 0000; the fifth pointer 90 and the sixth 

 pointer 7 cu. ft. If desired, the number of tenths, of cu. ft. 

 may be estimated by esti- 

 mating the position of the 

 pointer when it stands between 

 any two figures on the 10-ft. 

 dial. 



EMPIRE (w) 



TONAL MTER CC3 XIX 



ISiATONAL MTER C& 



NEW YORK, U.S.A. 



I9i8j8i0i9i7l 



CUBIC FEET 



FIG. 305. The straight reading register. 

 It reads 988,097 cu. ft. 



FIG. 306. The dial register 

 It reads 988,097 cu. ft. 



Exercise 96. Reading a Water Meter and Computing the Cost of Water 



Read the water meter at home or at the school on several successive 

 days recording carefully the reading each day. Ascertain the price 

 charged for water and compute the cost of each day's supply. 



IV. SANITARY PLUMBING 



586. Development of the Art of Plumbing. The art of 



modern plumbing has been developed within the past half- 

 century. The word plumbing is derived from the Latin word 

 plumbum, meaning lead. From the early days of plumbing, 

 lead pipes have been used to convey water, hence the name 

 plumbing has come to be applied to the entire art of supplying 

 water to buildings and to the disposing of the sewage. 



The Greeks and Romans, especially the Romans, made 

 much progress in developing the art of plumbing, although 

 many of their efforts would be considered very crude today. 

 During the 600 years from 300 B. C. to 300 A. D., the Romans 



