1904.
D. VAN NOSTRAND COMPANY,
NEW YORK.
LONDON:
PRINTED BY EDWIN JOHN DAVEY, 16, NEWCASTLE STREET, FARRINGDON STREET, E.C.
[Reprinted from the Chemical News, 1903, Vol. 88, p. 85 et seq.]
RADIO-ACTIVE SUBSTANCES.
INTRODUCTION.
The object of the present work is the publication of researches which I have been carrying on for more than four years on radio-active bodies. I began these researches by a study of the phosphorescence of uranium, discovered by M. Becquerel. The results to which I was led by this work promised to afford so interesting a field that M. Curie put aside the work on which he was engaged, and joined me, our object being the extraction of new radio-active substances and the further study of their properties.