The volume of natural gas utilized in the United States in 1916 was greater by nearly 20 per cent than the record production of the pre ceding year. Owing, however, to a reduction in the service price in some of the Western and Southern States, there was a slightly lower ratio (18.6 per cent) of increase in the value of the product. The yield amounted to 753,170,253,000 cubic feet (628,578,842,000 cubic feet in 1915), and the value to $120,227,468 ($101,312,381 in 1915). This sum may be better comprehended in its true relation to the mineral wealth of the country, if it is recalled that it is $27,000,000 greater than the value of all the gold produced in the United States in the same year.
Among the several States, the largest pro ducer was West Virginia, with 299,318,907,000 cubic feet; followed in order by Pennsylvania, with 129,925,150,000 cubic feet; Oklahoma, with 123,517,385,000 cubic feet; and Ohio, with 69, 888,070,000 cubic feet. Louisiana, Kansas and California each recorded a production of about 32,000,000,000 cubic feet. Nearly two-thirds of West Virginia!s production was piped into other States for utilization; and Oklahoma disposed of one-third of its yield in the same way. Pennsylvania, Ohio and Kansas bought practi cally all of this surplus, and New York bought a considerable share of Pennsylvania's output.
The gas was produced by 7,697 operators, from 37,989 active wells; 3,889 new wells having been added during the year to the 36,546 in pro duction at the beginning of 1916, and 2,4-46 hav ing been abandoned as no longer profitable. The area under control of the natural-gas pro ducers in 1916 totaled 12,899,781 acres; an in crease of 2,252,239 acres in the year.
Consumption and The natural gas output of 1915 was consumed by 7,939 manu factories, 10,419 other industrial plants and 2, 195,081 domestic consumers; the latter class consuming about 35 per cent of the total. The price to the manufacturers averaged 10.35 cents per 1,000 cubic feet. To the industrial plants it averaged 8.32 per 1,000 cubic feet; and to the domestic consumer, 28.32 cents per 1,000 feet. The prices which are thus expressed in an average figure varied from limits of 8.47 cents per 1,000 feet in Louisiana to $1.00 per 1,000 feet in Iowa; and some industrial plants in West Virginia using large quantities were sup plied at the price of 5.41 cents per 1,000 feet.
The above separation of ((manufacturing) from other industrial plants depends upon whether the gas is burned directly as fuel, as in the latter, or is used to produce power (steam or electric or gas engine), as in the former. About two-thirds of the 65 per cent used industrially was burned directly as fuel.
As used in the home, natural gas in itself is not dangerous to health. Tests made with canary birds, most delicately sensitive to poi sonous gases, showed that they breathed as large a proportion as 34 per cent in the air of a room without showing the least disturbance. They became drowsy when the percentage reached 49 per cent, but did not collapse until it was as high as 66 per cent; and then quickly revived when taken to the outer air. The risk from fire is less than when wood and coal are used. There have been some cases of asphyxia tion when a stove has been burned in a room without connection with the chimney flue, as it has been found that under these conditions the air in the room becomes more and more saturated with carbonic acid' and the vapors of water and depleted of oxygen. When this vitiated air passes again into the stove the com bustion is imperfect, the result being the forma tion of poisonous carbon monoxide (CO). There is more or less danger also from explo sion in the case of a mixture of natural gas with air from a leaky stove. A comparatively small percentage of gas makes an explosive mixture, the limits being 5 per cent (low) and 11.5 per cent (high).
Products of Combustion.— The products of complete combustion of natural gas are water and carbonic acid, slightly over two cubic feet of the former in the form of water vapor and about one foot of carbonic acid gas for each cubic foot of natural gas consumed; both are invisible and nearly odorless. Somewhat more than two cubic feet of oxygen are neces sary, but, owing to the air being composed of a larger percentage of nitrogen, a little over 10 cubic feet of air is required for thorough combustion.
It has been found that in a stove without a flue connection, especially if the air in the room becomes more or less saturated with carbonic acid and the vapor of.water from lack of fresh air, there is a small percentage of carbon mon oxide (q.v.) produced, which is a deadly and insidious poison, and if breathed by a man or an animal will soon cause death, even when a com paratively small percentage is present. When a small stovepipe connecting with a flue is used, no carbon monoxide is formed in the room, the greater portion of the products of combus tion being carried outside as the fresh air is drawn in to supply their place. On the other hand, where there is no flue connection or large opening for the free entrance of an abundance of fresh air, a number of fatal results and nar row escapes from asphyxiation have occurred.