CHEMISTRY. 295 



2. The Atomic Weight of Copper. 

 Mr. Arthur W. Phillips continued the study of the atomic weight of copper, 

 using samples of copper from widely different localities and widely different 

 geologic ages. He used a new method, the analysis of cupric chloride, and 

 succeeded in proving that copper from the Lake Superior district has, within 

 the limit of error, an atomic weight precisely equal to that of metal from the 

 much more recent deposits in Chile. 



3. The Compressibilities of Simple Salts. 

 Mr. Edouard P. R. Saerens, Belgium Research Fellow, continued the study 

 of the compressibilities of simple salts. He discovered that rubidium and 

 caesium bromide behave in an anomalous fashion, changing their state of 

 aggregation under comparatively low pressures, and he secured a wide variety 

 of other interesting data. This research has reached a state in which the 

 publication of the facts and of interesting relations between the several com- 

 pressibilities is desirable, and may soon be undertaken. 



4. The Properties of Liquid Water. 



Mr. H. Marshall Chad well continued the investigation of the physico- 

 chemical properties of water. To the data obtained in the preceding year, he 

 added careful determinations of the lowering of the freezing points produced 

 by various organic substances dissolved in water. A platinum resistance 

 thermometer with all known refinements was used in this work. The object 

 was to study the extent of the deviations from Raoult's Law exhibited by 

 various substances. Some of the aspects of the work are almost ready for 

 pubh cation. 



5. The Heats of Reaction of Slow Chemical Processes. 



Mr. Hans C. Duus has taken up the investigation of this subject (begun by 

 Mr. Oscar C. Bridgeman), has simpHfied and improved the apparatus, verify- 

 ing within a reasonable hmit of error the work of Mr. Bridgeman, and is now 

 ready to carry the investigation much further in the coming year. 



6. The Heats of Combustion of Carbon Compounds. 

 With the means now at command it is possible to improve the apparatus for 

 determining these important quantities. Mr. Stewart S. Kurtz jr. has 

 undertaken this task, and with an improved automatic adiabatic calorimeter 

 is beginning the systematic revision of the data on heats of combustion, which 

 furnish the chief basis of the thermo-chemistry of organic substances. 



7. Specific Heats of Solutions, Heats of Neutralization, and Heats of Dilution. 

 Our recent work on these topics brought results so interesting and valuable 

 as to indicate the desirability of continuing the investigation with other acids 

 and alkalis. This work has been undertaken by Mr. Frank T. Gucker jr. 

 He has constructed an elaborate twin calorimeter, operated and controlled 

 electrically, by which the specific heats of solutions can probably be deter- 

 mined with hitherto unattainable accuracy. These fundamental data must be 

 known accurately before heats of neutralization and heats of dilution can be 

 evaluated. Mr. Gucker proposes to continue the investigation next year. 



8. The Electrochemical Behavior of Barium Amalgams. 

 Mr. Paul A. Anderson has continued the study of the electrochemical 

 behavior of barium amalgams, which offered unexpected difficulties. Further 

 results have been obtained, but they are not yet quite conclusive. The chief 



