294: Scientific Intelligence. 



lowering of the atomic weight and density is due to the admix- 

 ture of a smaller amount of a substance with a lower atomic 

 weight. — Jour. Amer. Chem. ISoc, xxxviii, 109. h. l. w. 



2. Representative Procedures in Quantitative Analysis, by 

 Frank Austin Gooch. Svo, pp. 262. New York, 1916 (John 

 Wiley & Sons, Inc. Price f 2 net). — The presentation of a course 

 of instruction by an author of such eminence in researches in this 

 subject is naturally of the highest interest to teachers of analyti- 

 cal chemistry, and an examination of the book will show it to be 

 an important and valuable work. Scattered through the book are 

 numerous "experimental processes," or exercises for practice, 

 including the analysis of brass, of limestone, of silicates for alkali 

 elements, and some 40 or 50 determinations of metals and "ions" 

 (meaning acidic elements or groups). These processes are very 

 clearly discussed in relation to their essential features, underlying 

 principles, and varied applications. In addition to the exercises 

 for practice a good deal of valuable information is given in regard 

 to other methods of determination, among which, of course, the 

 methods that have been devised or studied by the author and his 

 students are prominent. Since the scope of the book is limited, 

 many important methods are not described ; for instance, for the 

 determination of carbon, li3 T drogen and nitrogen in organic sub- 

 stances the student is referred to other books. The separations 

 of metals and acid radicals from one another are discussed only 

 incidentally in connection with the determinations. The treat- 

 ment of the subject of volumetric analysis, particularly of the 

 iodometric processes, is very elaborate and excellent. The author 

 states that a large amount of space has been devoted to iodome- 

 tric processes both on account of the beauty and accuracy of 

 these methods, constantly growing in recognition, and because the 

 treatment in the more elementary text-books is usually scanty. 

 The book seems to be very well adapted to the purpose of inspir- 

 ing the student with a desire to attain high accuracy, and giving 

 him at the same time a good knowledge of the important prin- 

 ciples and facts of the science. In the opinion of the reviewer 

 the methods of weighing by the use of long swings of the balance 

 are less satisfactory than those where short swings are employed. 



H. L. W. 



3. The Molecular 'Volumes of Liquid Chemical Compounds, by 

 Gervaise LeBas. Svo, pp. 275. London, 1915 (Longmans, 

 Green and Co. Price $2.25 net). — This is the seventh to appear 

 of the important series of monographs on inorganic and physical 

 chemistry, edited by Professor Alexander Findlay, and intended 

 for the use of advanced students. The present volume deals with 

 an application of the theory of molecular volumes from the point 

 of view of Kopp to a study of the constitutions of organic com- 

 pounds chiefly. The author has taken up this line of work after 

 a period of about 25 years in which little or no advance has been 

 made. A very extensive study of molecular volumes has been 

 carried out and important results have been obtained, particularly 



