958
JOURNAL OF CHEMICAL EDUCATION
much cleaner and more accurate reduction with Pb is not considered. I t is illogical t o advocate the removal of Ni before the titration and not Fe. As20s is recommended for standardization of iodine because of the time required to dissolve pure Sn in HCI. Why not makc use of its quick solubility in concentrated H?S04? In the analysis of commercial Pb, apparently Bi is assumed to be abscnt. The chapter on clectrometric methods is bricf, Hildcbrand's apparatus being the only one considered. Each chapter is followed by its bibliography with a unique grouping of the references under headings which give an outline of the procedure. The total hibliography consists of about ROO0 references covering ssventy journals and numerous standard texts. The book is particularly h e from typographical errors and is wcll printed. I t is
A P R ~1930 ,
not recommended for student use except as a reference. With its enormous bibliography, it should be in every college library. It will appeal to all those who are actively interested in a diversity of analvtical work.
BULLETINS
Gradme in Industrial Schools and Classes. XI hl. l ' ~ . , v v r t ~Speclnlnrt . in lndustrral Education. U. S. Dept. of the Interior, Industrial Educelion Circular No. 25, Dcc., 1929. ,U. S. Govt. Printing Office, Washington. D. C. 20 pp. $0.05.
This pamphlet contains a general discussion of the grading situation and an annotated general bibliography on grading is included.
Bile-Calmette-Guerin a s Preventive Vaccine against Tuberculosis. By cultivating the tubercle bacillus through a long series of generations on a bile medium, Calmette, in association with Guerin, has succeeded in rendering the organism non-virulent though still possessing protective and immunizing powen. A preparation containing this modified tubercle bacillus under the name B.C.G. (thatis. "Rile-Calmette-Guerin") is now being tested on the large scale as a prwentive vaccine against tuberculosis both in the daily in man and in animals. According to r e ~ o r t swhich have appeared - . .press. Prof. Cantacuzene, of Bucharest, has carried out tests with this preparation in Rumania during the past three years, involving the inoculation of 17,535 persons, which incontrovertibly show the value of thc preparation. Out of more than 1000 children living in surroundings favorable t o the development of tubcrculosis who had been vaccinated, not a single case had been recorded, and no ill effect had followed vaccination or re-vaccination with B.C.G. I n Australia, Prof. Woodruff and Mr. Gregory have carried out experimental work with the B.C.G. vaccine as a preventive of tubcrculosis in cattle (lour. of the Council /or Scienti& end Induslvial Research, 2, 1929, p. 137; Melbourne: H. J. Green). A number of calves were inoculated with amounts of B.C.G. up t o 100 mgm. None of the animals showed any ill effects, the only lrsion produced being a small nodule which in course of time generally disappeared. Twenty vaccinated calves were afterward tested by intravenous inoculation of virulent tubercle bacilli t o determine their resistance toward virulent infection. Six of thcse animals died as a result of extensive tubcrculosis in about the same time as unvaccinated control animals. The remaining fourteen showed some clinical symptoms hut later became normal, and on slaughter, although some lesions of tuberculosis were found, in the majority these did not appear to be progressing. I t is concluded that B.C.G. vaccination confers some degree of resistance toward infection with virulent tubercle bacilli.-Nature
