of nitrogen in organic compounds was not included in the applications section even though it was mentioned briefly in part 2. There are remarkably few typographical errors in the book. The format is good and the organization is easy to follow. The most glaring omission seems to be in the section devoted to electrical circuits that have been suggested for flame photometers. Many of these diagrams have been reproduced without sufficient labeling of the component parts or legends to make them valuable to the reader. The hook should he useful to anyone who is contemplating the establishment of a laboratory devoted to &me photometric methods or to anyone engaged in research on the theory and applications of this method of analysis. Even though the authors make no claim that the bibliography is complete, they have tried to review practically all of the pertinent literature. CLARK E. BRICKER P s m o ~ m nU N L V B R B ~ Y PRINC~TOX. NEW JERSEY
THE DEVELOPMENT OF TITRIMETRIC ANALYSIS TILL 1806
E. Rancke Modsen, Technical University of Denmark.
G. E. C. Gads Forlag, Copenhagen, 1958. 238 pp. 16.5 X 24 em. Paper bound. D. er. 20. ANAL~ICA chemistry L is made up of such diverse branches that its history is best presented in specialized monographs such as the one being reviewed here This text was originally submitted to thefaculty of the University of Copenhagen as a doctoral dissertation and then put into English for publication. The translator ia P. Hardt, also a. Dane, a fact thet is sometimes reflected in the translation. The author made a thorough search of the literature, both periodicals and books, and his bibliography of 337 items is a valuable contribution to the history of this rather neglected topic. He not only digested what he read but in some cases tried out the eady procedures. A reading knowledge of German and French is assumed; the text contains many passages in these languages. I t is always difficult to establish the date of the beginning of any branch of science. Acid-base indicators occur, possibly for the first time in the published literature, in one of Robert Boyle's writings of 1663, and since the estahlishment of the endpoint is one of the vital features of titrimetry, Madsen uses this date as his starting point. Boyle used syrup of violets but extracts from other flowers, vegetables, berries, and woods were soon employed. Some had doubts that the change of color coincided with the point of sat(Continued on page AS61) JOURNAL OF CHEMICAL EDUCATION
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~ r a t i o nof the acid by the h a p ~and vice versa. The variance in the ohange point of different indicators was disoovered quite soon and Joseph Black introduced an indicator correction. Some used SOlutions of the indicators while others preferred indicator papers. The blue paper then commonly employed for wrapping sugar was found to serve admirably in this connection. When carbonates were being asaayed it was the 11soel practice to note the cessation of the effervescence either by eye or by ear. The clearpoint was ordinarily observed when precipitates resulted. The earliest uses of these quantitative procedures were in the examination of technical acids and alkalies. Mineral waters likewise were studied by such procedures. Many technical operators preferred t o rely on their prsetiesl experience and judged the strength of liquors of various kinds by taste, feel, and smell. In a good many instances the results were only compamtive but others were absolute in that standard solutions or primary standards were applied. The earliest redox reactions applied in titrimetry were the chlorine (hypoehlorite) bleaching of indigo. The titrator solutions w e n added and measured in the beginning hy drops or
VOLUME 35, NO. 8, AUGUST,
1958
by teaspoonfuls. Many preferred to weigh the solution of the material being added hefore and atter the t,itration. The pneumatic chemists had developed satisfactory devirm for measuring volumes of gases hut there seems to have been little or no need to measure small volumes of liquid with any degree of l exactness. The first g r a d ~ ~ n t wcylinder seems t o have been that of Guyton de Morveau (1783) which had a paper scale pasted to the glass. If, as was usuallv the ease, such measuring devices were also employed as the reaction vessel, the latter became a buret in a senso. The transfer pipet was due to Achard (1786). The development of the buret, conforming to the origin of the name, namely a flagon, was due to Descreizille (see mns JOURNAL 28, 508-19 (1951)). This instrument carried graduations made with a diamond or hydrofluoric acid, and the delivery of its contents was controlled by an airhole that could be covered by the operator's finger. Here finally was a. means of making a titration in the modern sense and so its date (1806) can be taken as the beginning of the modern era of titrimetry. This book is recommended to those who are interested in the history of analytical chemistry. RALPH E. OESPER U ~ l v s n s l r ror CINC~NXATI CINCINNATI. OHIO
