( I ) Evma, R. D..J 1ndu.f. Hyp and Toriol.. 25.253(1943). (2) Pnvste mmmunicetion with Monique Bardry. Char@. d.8 Archiueade I'1nstitut d" Radium. Fondation Curie, Paris, 1975. (3) Case. James T.. Amer J. RmntgewI.. S2.574!1959). (4) Finzi,N. S.,CIin.Rodiol., 12.143!1961). (5) Alexander, Peter, ',Atomic Radiation and Life: Penguin Books, London, 1967, p. 89. ikhoff.PhofogrophiJehp Rundsehou. 14,189iI9W). Rat ( 6 ) .p. 190. Giesel. F. Bor, 33,3569119W). Becquerel, Henri, end Curie, Pierre, Comptrs Rend., I32.128911901). rll,ipEVP."Madame Curio." ITmmloior Sheoan. Vincent). Doubldav Doran and Company, I n c . New ~ o r k1939,~. . 198. Ref. 191. p. 1290. Curie. Marie, "Pierre Curie," (Tramlotors: Kellogg, Charlotte, and Vernon) The Mscmillian Compsny, NewVork. 1923,p. 118. Looney. WilliamE.,Amrr. J. Roentgmoi.. 72.8381195B.pp.83b9. RcL (3).pp. 576-8: R e t (13).pp. 838-9. Ciilispie. C. C.. (Editor), "Didlonary of ScientificBiogrephy." Charles Scribner's som. Now York. 1972.~5"" Kirhu. H. W.. lsis. 62.. Ref. (B), p. 3570. ~ 1 h m . LK..N . Engl J. Mod., 286.348(19721
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The First Actinium Claim William H. Waggoner University of Georgia Athens, Georgia 30602 When nresent-dav chemists refer to actinium, the reference almost certainly is t o the radioactive elementisolated from nitchblende residues (1) . . hv . Andre Dehierne (1874-1949) in 1899. Nearly two decades earlier, however, a claim of the discovery of a quite different element for which the same name was suggested had been advanced as a result of an investigation of far more prosaic materials. Dr. Thomas Lamb Phipson (1833-1908) was an English analvtical chemist with a broad interest in things scientific. In d k , lohl, he puhlishvd a short account ( 2 ) of what he termrd '.a curious actinic phenumrnnn." The effect in question was a photwhernical one in which a painted Kate post was observed to rhnnre color, appearing hlack by day and white a t night. The process was &nplet& reversible and apparently was caused by a material in the white paint pigment reacting to sunlight. According to Phipson, this pigment was largely a mixture of co-precipitated BaS04 and ZnS, with smaller amounts of zinc and iron oxides and traces of lead, arsenic, and manganese. A darkening in the color from white through brown to a dark slate shade could he produced by exposing the pigment to direct sunlight for about 20 min. The orieinal hue was restored in darkness in several hours. No phosphorescence was observed and a plate of window glass nlaced over the white . piament prevented the darkening. A chemical examination of the pigment failed to reveal a n y unknown material but Phioson hedged the question as to the real cause of the phenomenbn. Hew& also caieful to state that the unknown metal. should there Drove to be one, was "to he called 'Actinium'." The manufacturer of the p i m e n t replied to Phipson (3), pointing out that the phenom&on cited was not new,dthough it had not been explained. More importantly, he questioned
580 / Journal of Chemical Education
Phipson's analytical data, especially the high percentage of zinc oxide and the presence of iron, lead, and arsenic. Several weeks later. a second letter appeared ( 4 ) . this one from an American &ment manufact&. More caustic than his Endish counterpart, Cawley also doubted Phipson's chemical i a t a and further stated that "I fmd that a she& of glass exerts no sensible protective action." ~ h i ~ s o nsecond 's note (5) added little new information except to say that he now believed the darkening to he caused by a reversible oxidation-reduction process involving some material associated with the zinc components of the pigment. "It is by no means impossible that new metallic element, Actinium, may be present in the specimens of white zinc examinrd hy me, andarruunt for the singular artinic phenomenon." Two months later, he reported (61that he had '.isolated the oxide and sulfide of the new metal in a state of tolerable purity." Actinium sulfide was obtained in about 4% yield and was found to he uhotosensiti\,e: the white oxide was not affected by sunlight. The metal &as not isolated. Cawlev. again responded (7). flatlv Phipson's . reiecting . claimsand remarking rhar h~"seernsco ha\?a perulinr talent for making - large - inductions from scanty and inadequate dam" Concerning the "new element ~ c t l n i u m ,. . . would not Phinsonium be a more suitable name if the new body should he iklated?" Shortly thereafter, Phipson informed the readers in the Chemical News (8)that he had isolated actinium by precipitating an ammoniacal solution with magnesium. The metal was said to form "a light grey deposit, which, by compression, becomes white like silver and extremely brilliant." I t was stahle under alcohol but oxidized slowlv in water and saline ~~solutions. His final report on this iubjeciappeared in 1882 (9) but was more concerned with zinc and glass than withactinium, per se. Twenty years elapsed before actinium was mentioned again in thk literature. In a footnote in his textbook, Mendeleeff (10) noted: "Amonest the metals accnm~auvine zinc which have . been named, gut not authentically separated, must be included the actinium of Phinson (1881) . . . As no further mention has been made of it since 1'882, its existence must be reearded as doubtful." Phipson's alleged discovery thus passed from the chemical scene by default. Had it proved to be a photosensitive metal, the name he had suggested would have been appropriate and Debierne would have had to look elsewhere in the classical languages for a suitable root. It is to he regretted that no one, including the o r i ~ n aclaimant, l ever confirmed the true nature of the material. ' ~~~
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Literature Cited
(41 Cswley,J.,Chem.NPUS,44.51 (1831). (51 Phipson, T. L.,Chem. News, 44.73 118811. 161 Phip~n.T.L..Chem. Nems, 44,138 11881);Bn'L.Ass" Reps.,51,603 (1881). (71 Caw1ey.J..Chom N e u , 44,167 (1881). (8) Phipron.T.L.. Chem.Neu8. 44,191 (18811. (9) Phipson,T.L.,Chem. Neyis, 45.61 (1882). (10) Mendeleeff, D.. "The P1incip1es of Chemistry: American Home Library company. New York. 1902. Pt. 3.p. 69.
