First, to conserve the supply of gas in every way possible. By conservation is meant not merely saving, but using in the most effective manner. This means that it is the duty of the gas company-under such conditions to remove every foot of gas from the ground that can be obtained.

Second, every appliance known to the art ought to be used to bring about the most economical mining of the gas and most effective method of transmission and distribution.

(J) A normal characteristic of every gas field is that its rock pressure decreases each year as the gas is being removed from the ground, as shown in graphical form in Fig. 3.

(K) In the face of a marked decline in rock pressure, the number of domestic consumers is on the increase (see Fig. 3), thus augmenting the difficulties under which the natural-gas company must operate in order to render service to its consumers. This means that as the fields grow

older it is necessary for the gas company to supplement the rapidly declining pressure by artificial means.

26. In the tests herein described two general classes of data were obtained, as discussed in the following two sections:

27. Simultaneous recording pressure-gage records were made, showing actual routine operating conditions in various parts of the field; 17 standard recording pressure gages with 8-in. charts were used for this service; 290 recording pressure-gage charts, made at 43 different places. in the field, were obtained during the months of August, September, October, November and December, 1913.

28. The relation of the natural or open flow to actual line flow from various wells was obtained by the use of ordinary Pitot tubes. The open flow was determined by the Pitot tube arrangement shown in Fig. 7. A short length of pipe was screwed into the top of the well gate, and as the well discharged into the atmosphere the dynamic pressure corresponding to the velocity of the gas was measured in the U-tube of the pressure gage shown at the right. The actual line flow was determined by the Pitot tube arrangement shown in Fig. 8. This was placed in the discharge line of the well when the well was working under routine conditions. The static pressure was observed by the spring pressure gage at the top and the dynamic differential pressure was obtained by the U-tube fluid gage as shown. A square-jawed micrometer caliper was used for measuring the difference in liquid elevations in the U-tubes. The volume passing both Pitot tubes was computed by the ordinary Pitot tube tables. A summary of some of the tests is given in Fig. 9.

29. The precautions taken to secure accuracy were as follows: All the recording gages used were new, and these and all other gages used in this series of tests were carefully calibrated before being placed into service and during service by testing on a standard gage-testing apparatus.

A dependable watch, running on central standard time, was used as the basis for starting the clocks of the various recording gages. This watch was carefully checked at least three times a week against the standard time furnished by the Western Union Telegraph Company, and every time a chart was set on a gage the clock was carefully set to correspond with the correct time by the watch. In this way it was an easy matter to attain synchronous action from all the recording gages. Each recording

gage, when in service, was also locked and sealed, to prevent tampering. Every chart in this entire series of tests was set and removed from the gage by the author.

30. The data obtained by the recording gage charts were plotted on 116 sheets of uniform size and scale, of which two are given in Figs. 10 and 11. Each sheet gives the results of 48 consecutive hours of service. The gage-pressure scale is given on the left-hand side of the sheet and the

absolute-pressure scale on the right-hand side, while the dates are always marked at the bottom.

31. The observations and data obtained led to the following conclusions:

(A) Ordinarily only a relatively small percentage of the natural flow may be obtained from a natural-gas well under routine operating condi

IN KNOX AND LICKING COUNTIES, OHIO WHERE TO THE ELEVATION ABOVE SEA LEVEL
THIS IS THE ATMOSPHERIC PRESSURE SURES IN LBS. PER SQ. IN.

FIG. 10.-SHORT RANGE OF LOW PRESSURES IN "MILLER INTAKE LINE" OF OHIO FUEL SUPPLY Co., DISCHARGING IN HOMER COMPRESSING STATION, BASED ON SIMULTANEOUS RECORDING PRESSURE-GAGE RECORDS.

tions, even when such a well is discharged into the intake line to a gascompressing station.

(B) That this Ohio field is not made up of one large "connected and continuous reservoir," but rather composed of many separate and discontinuous reservoirs, is evident from:

(a) The large number of dry holes drilled.

(b) The large number of wells that have been abandoned in close proximity to producing wells.

(c) The continuous difference in rock pressure in adjacent wells that have been shut in for a period of years.

(d) The marked variation in working pressures of adjacent wells. (e) The marked variation in rock pressure in different parts of the field.

(C) The diminution in rock pressure has simply been the normal

FIG. 11.-WORKING PRESSURE RELATIONS OF GAS WELL OF UPHAM GAS Co., DISCHARGING INTO LINE BY NATURAL ROCK PRESSURE WITHOUT COMPRESSORS, AND ADJACENT GAS WELL OF OHIO FUEL SUPPLY CO., DISCHARGING INTO INTAKE LINE TO HOMER GAS COMPRESSING STATION BASED ON SIMULTANEOUS RECORDING PRESSURE-GAGE RECORDS.

decrease that is inevitable with the removal of the gas from the various reservoirs.

(D) The water troubles that are experienced with certain wells in the field are due to the decrease in pressure in the local reservoir supplying the particular well, caused by the removal of the gas from such reservoir, regardless as to whether such removal was by letting the wells discharge into lines without compressors, or with compressors.