LOS ANGELES DISTRICT: PREVIOUS REPORTS. 
141 
out of the ground at numerous points. It hardens on exposure to the air and becomes 
mixed with sand and dust blown into it, and is then known as “brea.” The holes 
through which the bitumen comes to the surface are not large, few being more than 3 
or 4 inches in diameter. On removing the tarry substance from the holes, by repeatedly 
inserting a stick, the empty cavity was very slowly filled up again. At one place there 
was a pit several yards square and 6 or 8 feet deep, from which the tar had been taken, 
but it was filled with water at the time of our visit in consequence of late heavy rains. 
The brea is used almost exclusively for covering roofs at Los Angeles, selling (in 1861) 
at the springs for $1 per barrel, the purchaser collecting it himself, which is done by 
digging a pit 2 or 3 feet deep by the side of one of the holes from which the tar is issuing 
and letting it lill up. A very large amount of the hardened asphaltum, mixed with 
sand and the bones of cattle and birds, which have become entangled in it, lies scat¬ 
tered over the plain. Before 1860 the experiment of shipping it to San Francisco for 
the purpose of distilling burning oil from it had been tried, without success, at least 
in a pecuniary point of view. 
A report on the geology of a portion of southern California, by 
Jules Marcou ; a a paper on the petroleum, asphaltum, and natural 
gas of California, by W. A. Goodyear, 6 and a paper on the origin, 
composition, etc., of California petroleum, by F. SalatheJ complete 
the list of more or less important papers bearing on the geology and 
oil industry of the region about Los Angeles up to 1897. 
In 1897 W. L. Watts issued the first d of his two reports largely 
devoted to the Los Angeles and adjacent oil districts. In this report 
he gives a brief outline of the geology of the territory discussed; lists 
and logs of productive, test, and abandoned wells, and notes on 
miscellaneous subjects, such as fossils of the oil-bearing formations, 
production, uses, and chemical and physical properties of the oil, 
refineries, drilling machinery, etc. Watts’s second report, 6 although 
covering the California oil districts in general, is still largely given over 
to the fields of Los Angeles, Ventura, and Orange counties. Chapters 
are devoted to a discussion of the structural conditions pertaining to 
the occurrence and distribution of petroleum in California, the uses 
and chemical and physical characters of the oil, etc., and in addition 
there are brief reports on the fossils of the oil-yielding formations hv 
J. C. Merriam, on the Humboldt County oil fields by F. M. Anderson, 
and on the oil-yielding formations of San Luis Obispo and Monterey 
counties by II. W. Fairbanks. 
A paper by G. II. Eldridge/ in the Contributions to Economic 
Geology for 1902, is of interest not only on account of its comprehensive 
though short description of the individual fields, but also because it 
a Ann. Rept. U. S. Geog. Surv. W. 100th Mer., 1876, Appendix II 1, pp. 158-172. 
ft Seventh Ann. Rept. California State Mineralogist, 1888, pp. 63-114. 
cThirteenth Ann. Rept. California State Mineralogist, 1896, pp. 656-661. 
d Oil and gas yielding formations of Los Angeles, Ventura, and Santa Barbara counties: Bull. Cali¬ 
fornia State Mining Bureau No. 11, 1897, pp. x+94, 35 figs. 
e Oil and gas yielding formations of California: Bull. California State Mining Bureau No. 19, 1900, pp. 
236, 26 text figs., 35 half tones, 13 maps. 
/ The petroleum fields of California: Bull. U. S. Geol. Survey No 213, 1903, pp. 306-321. 
