450 



SCIENCE. 



[N. S. Vol. I. No. 17. 



5. A. Linkage Showing the Laws of the Refrac- 

 tion of Light : A. M. Mayee. 



6. On the Color Relations of the Atoms, Ions 

 and Molecules : M. Caeey Lea. 



7. Mechanical Literpretations of the Variations 

 of Latitude : E. S. Woodward. (Intro- 

 duced by S. C. Chandler.) 



8. On a New Determination of the Nutation- 

 Constant, and some allied topics : S. C. 

 Chandler. 



9. On the Secular Motion of a Free Magnetic 

 Needle : L. A. Bauer. (Introduced by C. 

 Abbe.) 



10. On the Composition of Expired Air, and 

 Its Effect Ujion Animal Life: J. S. Billings. 



11. Systematic Catalogue of European Fishes : 

 Th. Gill. 



12. The Extinct Cetacea of North America: E. 

 D. Cope. 



13. On the Application of a Percentage Method in 

 the Study of the Distribution of Oceanic Fishes. 



A. Definition of Eleven Faunas and Two 

 Sub-faunas of Deep Sea Fishes. 



B. The Relationships and Origin of the Carri- 

 beo-Mexican and Mediterranean Suh- 

 faunas : Gr. Brown Goode. 



14. On the Two Isomeric Chlorides of Ortho- 

 sidpho-benzoic Acid : Ira Remsen. 



15. On Some Compounds Containing two Hal- 

 ogen Atoms in Combination with Nitrogen : 

 Ira Remsen. 



16. Presentation of the Watson Medal to Mr. 

 Seth G. Chandler, for his Researches on the 

 Variation of Latitudes, on Variable Stars, and 



for his other works in Astronmny. 



17. Biographical Memoir of Dr. Leivis M. Ruth- 

 erf urd : IB. A. Gould. 



18. Relation of Jupiter'' s Orbit to the Mean 

 Plane of Four Hundred and One Minor 

 Planet Orbits : H. A. Newton. 



19. Orbit of Miss MitchelVs Comet, 1847, VI: 

 H. A. jN"ewton. 



The officers elected were as follows : Presi- 

 dent, Prof. Wolcott Gibbs ; Vice-president, 

 Gen. F. A. Walker ; Home Secretary, Prof. 

 Asaph Hall ; Foreign Secretary, Prof. A. 



Agassiz ; Treasurer, Dr. John S. Billiugs ; 

 additional members of the Council, Prof. 

 George J. Brush, Prof. George L. Goodale, 

 Dr. B. A. Gould, Prof. O. C. Marsh, Prof. 

 Simon Newcomb and Prof. Ira Remsen. 



The new members elected were Prof. W. 

 L. Elkin, professor of astronomy in Yale 

 Observatory; Prof. C. S. Sargent, professor of 

 botanj' in Harvard University ; Dr. W. H. 

 Welch, professor of pathology in Johns 

 Hopkins Universitj^, and Prof C. 0. Whit- 

 man, professor of biology in the University 

 of Chicago. The foreign associates elected 

 were Prof. Rudolph Leuckart, professor of 

 zoology in the University of Leij^sic ; Prof. 

 Julius von Sachs, professor of botanj' in the 

 University of Wiirtzburg, and Prof. Sophus 

 Lie, professor of mathematics in the Uni- 

 versity of Leipsic. 



The Barnard Medal was awarded to Lord 

 Rayleigh for his discoveiw of argon, and 

 the Watson Medal to Professor S. C. Chand- 

 ler for his researches on the variation of 

 latitude and other subjects. 



The autumn meeting of the Academy 

 will be held at Philadelphia, beginning Oc- 

 tober 29. 



ABTEUR CAYLEY. 



How Professor Caylej' touched everj^thing 

 mathematical, and touched notlung which 

 he did not adorn, may be illustrated by the 

 following unpublished letters, which were 

 the first expression of discoveries that have 

 siace taken their permanent place in our 

 best text-books. They are both the outcome 

 of the sudden and fruitful interest in linkage, 

 dating from S3dvester's interview with 

 Tchebychev, when, leaving behind him the 

 diagram of the now celebrated Peaucellier's 

 Cell, the illustrious Russian gave in parting 

 the characteristic advice: "Take to kine- 

 matics; it Avill repay you; it is more fecund 

 than geometry ; it adds a fourth dimension 

 to space." 



I -will transcribe the letters exactly, not 



