818 



SCIENCE 



[N. S. Vol. XLIII. No. 1119 



tative analysis by the principles of physical 

 chemistry and thus made it an introduction 

 to the latter subject. Others have, even more 

 recently, demanded a quantitative interpre- 

 tation of results and thus made the course an 

 introduction to quantitative analysis. 



There is no longer room in a modern course 

 in chemistry for any extended treatment of 

 qualitative analysis without great use of the 

 fundamental principles of physical chemistry. 

 Tor that matter, these principles are taught in 

 general chemistry, but they are not thoroughly 

 digested in the iirst year, probably because of 

 a first-year tendency to bolt rather than to 

 masticate such food. After the somewhat 

 hurried meals on countless viands in the gen- 

 eral subject the student is ready to settle down 

 in the second year to a more thorough assimi- 

 lation. Yet if at this stage he is given an end- 

 less round of unknowns in the old qualitative 

 system he soon learns all the manipulation re- 

 quired, gains all there is for him from the 

 classification, and then spends his time for 

 months learning one new reaction after an- 

 other in true encyclopedic fashion without any 

 fiorther great advance in general principles. 

 He learns something more, of course, and may 

 even enjoy the game indefinitely; but his 

 time, after a limited amount of such work, 

 could be spent to better advantage. A full 

 year of this repetition work has been given 

 in some colleges — crowding out more valuable 

 training. 



The attempt to make qualitative analysis 

 approximately quantitative has the great de- 

 fect of " delaying the game." The same dis- 

 cipline can be given later much more rapidly 

 and effectively in genuine quantitative anal- 

 ysis. There are not enough new principles 

 learned by this slow method to justify the very 

 considerable time required. Furthermore, the 

 points of teaching value are repeated ad infin- 

 itum without great additional gain. 



In a word, qualitative analysis has had too 

 large a place in the chemical curriculum. 

 Far better to give the student a limited 

 amount of this and advance him more rapidly 

 by other courses. He will then be able to add 

 to his knowledge of qualitative methods as re- 

 quired, independently of his teacher. 



There are now a few excellent texts treating 

 qualitative analysis from the viewpoint of 

 physical chemistry, but they could be improved 

 by the addition of laboratory drill, using accu- 

 rate demonstrations of some of those funda- 

 mental principles on which students look with 

 awe — or doubt — in the first year. True, such 

 experiments are not qualitative at all, but it 

 is to be hoped the instructor would rather 

 teach advanced chemistry effectively under 

 any name than secure the barren triumph of 

 remaining within the narrow limits of quali- 

 tative analysis. Call it analytical, advanced 

 inorganic — the name matters little. 



Many " laws " were gulped down in general 

 chemistry with an antiferment of skepticism 

 to interfere with their proper digestion. To 

 require these students in their second year 

 actually to duplicate the historical experiments 

 which gave occasion for those " laws " is to 

 lay solid foundations and kindle the spark of 

 inspiration. 



Professor W. H. Chapin, in our laboratory, 

 has developed such a course and it is well 

 worth the attention of other teachers. Molec- 

 ular theory, atomic theory, solutions, the elec- 

 trochemistry of solutions, colloids, equilibrium, 

 oxidation and reduction, complex ions and 

 other topics of like nature are treated some- 

 what as in the splendid book of Stieglitz. But 

 Professor Chapin goes farther and advocates 

 the use of accurately performed experiments 

 on the heat of neutralization, Boyle's law, com- 

 bining weights, valence, Faraday's law, col- 

 loids, speed of reaction. Oxidation and reduc- 

 tion are illustrated by volumetric relations be- 

 tween standard solutions of oxidizing agents 

 and reducing agents. The determination of 

 molecular weights in two ways, the abnormal- 

 ity of freezing point lowering as an evidence 

 of ionization, and other experiments of this 

 type are found stimulating. 



This work is followed by a rather brief 

 treatment of qualitative analysis taught to 

 illustrate the principles of equilibrium, com- 

 plex ions, amphoteric hydroxides, etc., rather 

 than as an end in itself. It is noteworthy that 

 the previous drill in fundamentals gives the 

 student greater facility in learning the quali- 



