DISTRIBUTION. 6l 



the earliest consumers begin to complain that the gas is 

 not so good as it used to be ? 



The initial pressure and the value of a are matters 

 determined once for all by the original design of the plant. 

 Suppose a manager having 500 yards of 4-inch pipe and a 

 maximum available initial pressure of 25-tenths is called 

 upon to supply 2,000 cubic feet per hour at 20-tenths, he 

 cannot do it. The remedy is to take up the 4-inch pipe 

 and put down a 5 -inch. 



An established rule as to the depth at which main pipes 

 should be laid is, or was, a clear 18 inches, and sometimes 

 only 15. But there is good reason for re-considering this 

 matter. The heavy motor and traction engine is a power in 

 the land. Even in the smallest villages the large engine, 

 with its train of two or three timber trucks, loads of 

 bricks, furniture, pantechnicons, etc., is seen to pursue it's 

 lumbering, noisy way, and the heavy studded wheels cause 

 a perceptible vibration as they pass. The road authorities 

 have developed a fancy for 20-ton road rollers, and do not 

 always eni| loy either the quality or the thickness of road 

 metal that is consistent therewith. And they believe in 

 making up the roads with a rise of several inches on the 

 crown, into the shape, in section, of the segment of a circle. 

 Sometimes this result is obtained by re-metalling the centre 

 of the road only and rolling down the sides. I have known 

 roads to be put down three inches or so at the gutters, and 

 the authorities did not seem at all perturbed at the risk of 

 injury to the service pipes. Mains and services do not 

 have such an easy and comfortable time as they used to 

 get, but are subject to more strain and to more 

 vibration. 



In country districts it is rarely practicable to have more 

 than one line of main in a road. In towns with wide streets, 



