32 



SCIENCE 



[N. S. Vol. XXVIII. No. 705 



Professor D. W. Hering in the chair. Professors 

 Lamb, RosanoflF and Breithut read a paper on 

 "A New Method of Measuring Partial Vapor 

 Pressures in Binary Mixtures." 



On Monday, March 16, Professor W. Campbell 

 read some " Notes on Metallography applied to 

 Engineering." The methods of preparing speci- 

 mens, development of structure, microscopic ex- 

 amination and photographing the specimen were 

 briefly reviewed. The structure of metals, ingot- 

 ism and grain structure, the effects of strain and 

 of annealing were demonstrated and the constitu- 

 tion of alloys, mattes, speisses, etc., taken up. 

 The carbon-iron series, the graphite-austenite and 

 cementite-austenite groups were discussed and 

 illustrated. Examples of structure were given; 

 wrought iron vs. low carbon steel, good and 

 bad material; working and annealing of mediiun 

 carbon steel; rails and examples of their failure; 

 steel tyres and shelling out; the structure of 

 hypereuteotic steels and their change with heat 

 treatment; cast iron, gray, mottled, white, spiegel- 

 eisen; cementation and blister steel; malleabil- 

 izing and the formation of temper carbon. 



The application of metallography to economic 

 geology was shown by demonstrating the para- 

 genesis of certain mixed sulphide ores, of silver 

 ores from Cobalt, Ont., of the Butte copper ores, 

 of typical " enrichment zones." The constitution 

 of so-called nickeliferous pyrrhotites and of cer- 

 tain complex opaque minerals was shown. Many 

 lantern slides were used to illustrate the paper. 



A sectional meeting was held on Monday, May 

 18. Dr. J. P. Simmons presented a " Note on a 

 Curious Effect produced by the Explosion or 

 Detonating Gas." When a mixture of oxygen and 

 hydrogen is exploded in a tube, the inside of which 

 is coated with a thin layer of water, perfect rings 

 are formed. The same phenomenon has been 

 noticed when the same kind of a gas mixture is 

 exploded in a tube, the inside of which is coated 

 with a thin layer of wax. This is a heating effect, 

 since the rings formed in the tube covered with 

 wax are made apparent by the melting of the lat- 

 ter substance. This periodic heating is probably 

 due to compressions arising from either soimd or 

 explosion waves. 



W. Campbell and P. F. Bohler read a paper on 

 the heat treatment of carbon tool steels. The 

 various constituents of unhardened and hardened 

 high carbon steels were first classified, cementite, 

 pearlite, ferrite, graphite, austenite, martensite, 

 troostite, osmondite and sorbite, and the views of 

 the different authorities on their constitution 



given in tabular form. The plan of study em- 

 braced (1) heating to various temperatures and 



(a) slow cooling, (6) quenching, (c) tempering; 



(2) the effects of forging temperature and quench- 

 ing temperature, to see whether the structure 

 gave any evidence whether overheating had taken 

 place during forging at the works of the manu- 

 facturer or during reheating for hardening at the 

 user's, in the case of faulty material ; also whether 

 this persisted after tempering. Only the maxi- 

 mum forging temperature left any traces after 

 quenching and this was much above that used in 

 practise. Tables and curves showing variation 

 of physical properties with heat-treatment were 

 given, and the various structures illustrated by 

 numerous lantern slides. 



li'rofessor Charles L. Poor presented two papers 

 by title, ( 1 ) " An Investigation on the Figure of 

 the Sun and of Possible Variations in its Size 

 and Shape," ( 2 ) " The Photoheliometer." 



William Campbell, 

 Secretary 

 Columbia Univebsitt 



the chemical society of washington 



At the 183d meeting of the Chemical Society of 

 Washington, held at the Cosmos Club, May 14, 

 1908, the following papers were presented : " In- 

 fluence of Fine Grinding on the Water and Fer- 

 rous Iron Content of Minerals and Rocks," by 

 W. F. Hillebrand, and " Technical Value of Wood 

 Turpentine," by F. P. Veitch. 



Mr. Bailey Willis, of the Washington Academy 

 of Science, addressed the society in regard to a 

 proposed scientific weekly. The following resolu- 

 tion was then adopted: 



Resolved, That it is the sense of the society 

 that the new journal is desirable and, further, 

 that it will be welcomed by this society. 



The meeting was presided over by President 

 Joseph S. Chamberlain, and the attendance was 

 48. President Bogert also addressed the society 

 on problems of general interest to the members 

 of the Chemical Society. 



A special meeting of the society was held at the 

 George Washington University Lecture Hall on 

 May 9, 1908. President Chamberlain introduced 

 Dr. C. A. Ernst, the speaker of the evening, who 

 gave an address on " Viscose and Artificial Silk." 

 The lecturer showed many samples of artificial 

 silk, and explained the process carried on at the 

 Genasoo Silk Works of Lanadowne, Pa. The at- 

 tendance was 65. J. A. LeCleec, 



