1 86 



POPULAR SCIENCE MONTHLY. 



Concerning this apparatus many erroneous notions prevail. One 

 of these is that a householder may burn thousands of feet of gas 

 without cost to himself, provided he keeps the company in blissful 

 ignorance of the employment of gas for heating purposes upon his 

 premises. The demonstration of the falsity of this idea lies within the 

 reach of any one who will take the trouble to read his own meter on 

 those days on which the company's indexer pays his monthly visits. 



Figs. 1, 2 and 3 represent different states of the index usually 

 employed on the three, five and ten light meters, the sizes commonly 

 found in our dwellings. The smaller dial, placed centrally above the 

 other, is known as the 'proving dial,' and, being used merely for 

 testing purposes, is not considered in reading the gas consumption. 

 Although the index dials vary in nomenclature as well as in number, 

 it is generally safe to consider that if the name is placed above the 



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Fig. 1.— Reads 3,300 Cubic Feet. 



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Fie. 2.— Reads 19,800 Cubic Feet. 

 The apparent reading is 29,800. 

 The gearing of the indexing mech- 

 anism is not especially delicate, and 

 it frequently happens that the dial 

 of one denomination begins to re- 

 cord before the hand of the next 

 lower denomination has made a 

 complete revolution. 



Fig. 3. — Reads 19,800 Cubic Feet. 



dial a complete revolution of the pointer is required to register the 

 amount of gas indicated by the name; whereas if the name is placed 

 below the dial each numbered division of the dial represents the amount 

 corresponding to the name. If doubt still exists as to the value of each 

 division of the lowest or right-hand dial, remember that no meter index 

 is designed to read less than one hundred cubic feet for each division 

 of the circle. 



After one has indexed his own meter for a month or two he is in 

 a position to begin checking the bills presented. The 'present state of 

 meter' and the 'previous state of meter' are always specified, and the 

 mere subtraction of the former from the latter gives the consumption. 

 This is not invariably the case, however. After a meter has registered 

 its maximum reading — 100,000 in the smaller sizes — it passes over the 

 zero point and begins to build up a new record. This happens at 



