478 Scientific Intelligence. 



in the ore beds producing local differences which are equalized in 

 mixing large quantities. — Jour. Amer. Chem. *Soc, xxxvi, 2066. 



H. L. W. 



2. A Neio Method for the Precise Standardization of Hydro- 

 chloric Acid Solutions. — Launcelot W. Andrews has devised 

 an ingenious and simple method for the accurate standardization 

 of volumetric hydrochloric acid solutions. It depends upon add- 

 ing a measured quantity of the acid solution to an excess of pure, 

 dry silver nitrate in a dish, evaporating to dryness, drying at 240° 

 C, and determining the loss in weight due to the conversion of a 

 part of the silver nitrate to chloride. As the process involves no 

 transferring or washing of a precipitate, it is very accurate as well 

 as easy to carry out. The author recommends the use of a com- 

 panion dish containing no silver nitrate, in which the same quan- 

 tity of acid solution is evaporated in order to make a correction 

 for any non-volatile impurities that the liquid may have derived 

 from glass vessels. The precaution should be taken that the silver 

 nitrate is entirely free from the ammonium salt, and it should be 

 dried at 240° C. before the weight is taken. A short stirring rod 

 should be weighed with the silver nitrate, in order that it may be 

 used after the addition of the hydrochloric acid, and the rod 

 should remain in the dish throughout the operation. The dishes 

 should be covered with light watch-glasses while being weighed. 

 The author states that he has employed the method for several 

 years, and gives the results of four determinations where, for the 

 sake of the greatest accuracy, the acid solution was weighed. 

 These results show surprisingly small variations, the results being 

 0*53063, 0-53062, 0'53095 and 053054 in terms of normality.— 

 Jour. Amer. Chem. Soc, xxxvi, 2089. h. l. w. 



3. Introductory Notes on Quantitative Chemical Analysis /by 

 Charles William Foulk. 8vo, pp. 250. New York 1914 

 (The McGraw-Hill Book Company. Price, $2.00 net).— This is 

 the third edition of a useful book for students of quantitative 

 analysis. Its plan is unusual, as the larger part of the book is 

 devoted to a general discussion of operations, many of which are 

 taken up in great detail. For instance, 16 pa^es are devoted to 

 the balance and weighing. In connection with this part it may 

 be observed that it seems very unfortunate that a long swing of 

 the balance pointer is recommended for ordinary weighing instead 

 of a very short swing, since the use of the latter is much less 

 laborious, and certainly just as accurate if a good balance is 

 employed. However, the advice given in this book appears to be 

 excellent in almost every particular. 



The practice work laid out in the book includes both gravi- 

 metric and volumetric operations. The course is not a very 

 extensive one, but as far as it goes the directions are full in 

 regard to every detail, with frequent references to the general 

 part of the book, and many explanatory notes. h. l. w. 



4. Elementary Household Chemistry, by John Ferguson 

 Snell. 12mo, pp. 307. New York, 1914 (The Macmillan Com- 



