Alexander Macfarlane was born April 21, 1851, at Blairgowrie,
Scotland. From 1871 to 1884 he was a student, instructor and
examiner in physics at the University of Edinburgh, from 1885
to 1894 professor of physics in the University of Texas, and from
1895 to 1908 lecturer in electrical engineering and mathematical
physics in Lehigh University. He was the author of papers on
algebra of logic, vector analysis and quaternions, and of Mono-
graph No. 8 of this series. He was twice secretary of the sec-
tion of physics of the American Association for the Advancement
of Science, and twice vice-president of the section of mathematics
and astronomy. He was one of the founders of the International
Association for Promoting the Study of Quaternions, and its
president at the time of his death, which occured at Chatham,
Ontario, August 28, 1913. His personal acquaintance with
British mathematicians of the nineteenth century imparts to
many of these lectures a personal touch which greatly adds
to their general interest.

ALEXANDER MACFARLANE
From a photograph of 1898

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