RT Journal Article SR Electronic T1 The contraction of molten rock JF American Journal of Science JO Am J Sci FD American Journal of Science SP 498 OP 499 DO 10.2475/ajs.s3-42.252.498 VO s3-42 IS 252 A1 Carl Barus YR 1891 UL http://www.ajsonline.org/content/s3-42/252/498.abstract AB