Next to petroleum the two most important mineral products were natural gas gasolene and natural gas. Production of the former increased in value from $14,460,000 in 1924 to $18,346,000 in 1927 but declined to 366,515,000 gal., valued at $11,562,000, in 1933. Peak production was reached in 1931 with 426,695,000 gal. Production of natural gas increased in value from $13,748,000 in 1924 to $88,265,000 in 1933. By quantity, the output rose from 74,535 M. cu. ft. in 1923 to a peak of 517,880 M. cu. ft. in 1930, and then fell to 456,832 in 1932 and 475,691 in 1933. One of the most remarkable industrial developments of Texas in the decade 1925-35 was the rapid extension of gas pipe lines from the State's deposits to distant markets. Gas production is principally from the great field north of Amarillo, from Palo Pinto, Clay and East land counties in North Central Texas, and from Harrison county in East Texas. There were 1560 natural gas wells in 1933.
Cement production in 1933 was 3,091,071 bbl., valued at $5, 268,605. Clay products were valued at $6,298,045 in 1925 and at $1,083,051 in 1933. Clays susceptible of commercial develop ment have been found in nearly every county of the State and in great variety. The increase in highway and other construction produced a greater demand for sand and gravel, the 1933 output being valued at $2,264,905. Stone products in 1933 were valued at $1,170,464. Limestone is used extensively in the making of cement, but is also quarried for building stone and burned in kilns for the making of lime. Limestone sold or used by Texas pro ducers in 1933 was valued at $850,904 and the output of lime at $339,035, both figures being less than half the pre-depression totals. There is a large industry in Texas manufacturing plaster, wall board, cement, roofing and other materials from gypsum. The State ranked fourth in point of output and fifth in point of value of gypsum in 1925, the value being by 1933 the output had declined to 112,105 short tons, valued at $1,058,869. Asphalt is found in the native state and also manufactured from petroleum. In 1933 native asphalt output was 126,069 short tons, valued at $353,847. With the closing of the Louisiana sulphur mines in 1924 Texas remained the only large sulphur-producing State in the Union. In 1933 the sulphur output was long tons, valued at $27,139,482, compared with the total United States output of 1,637,386 long tons, valued at $29,500,000.
The abundant supply of petroleum and natural gas for fuel has retarded the development of coal deposits. Texas has a fair supply of bituminous coal which is found in north-central and middle-western Texas and also of sub-bituminous or cannel coal found in Webb and Maverick counties in south-west Texas along the Rio Grande. In addition there is an almost inexhaustible sup ply of lignite, the belt extending across the State from the vicinity of Laredo on the Rio Grande to north-east Texas, covering about 6o,000 sq.m. and having an estimated quantity of 30,000,000,000
tons unmined. The bituminous and sub-bituminous areas cover about 25,000 sq.m. and contain, it is estimated, 8,000,000,000 tons. Coal produced in 1933 totalled 821,878 short tons valued at The chief metal of commercial importance in 1932-33 was lead, the output being valued at $1,020,000 and $222,000 respectively. Silver ores are found in Culberson, Hudspeth and Presidio coun ties in the Trans-Pecos province. Copper production was 7,000 lb., valued at $441,000 in 1932 and 2,000 lb. worth $128,000 in 1933. There is a steady production of mercury, Texas producing about one-fourth of the annual production of the United States.
There are extensive iron deposits easily available, but production is slight chiefly because of lack of coking coal. Manganese, zinc and tin ores are found, but are only slightly developed.
The period 1920-35 was a difficult one for agriculture, how ever, because of the sharp depression of prices which occurred in 1921 and recurred with even greater severity in 1930-33. The total value of all farm property, which between 1910-2o had in creased from $2,218,645,000 to fell to 867,000 by 1925 and then increased to $4,234,315,699 in 1930. Between 1925 and 1930 farm land increased in value $437,712,706 to a total of $3,062,869,535; farm buildings increased $114,423, to farm implements and machinery increased $40,287,687 to $182,186,189; and farm live stock increased $170, to The decrease in the value of farm land and buildings per acre was from an average of $32.45 in 1920 to $27.77 in 1925 and $28.85 in 1930.