RT Journal Article SR Electronic T1 On irregularities in the amplitude of oscillation of pendulums JF American Journal of Science JO Am J Sci FD American Journal of Science SP 254 OP 255 DO 10.2475/ajs.s3-24.142.254 VO s3-24 IS 142 A1 C. S. Peirce YR 1882 UL http://www.ajsonline.org/content/s3-24/142/254.abstract AB