SCIENCE. 



iii 



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SCIENCE 



A. WEEKLY JOURNAL OF SCIENTIFIC PROGRESS 



Vol. II. No. 42, ------- April! 6, 1881. 



CONTENTS. 



Cosmical Evolution (Edit.); The Sea-Side Laboratory ; American Chemical Society; On some Phenomena presented by 

 Vortex-Rings, by Prof. A. E. Dolbear ; The Co-efficient of Safety in Navigation, by Prof. W. A. Rogers; Notes on 

 Chicken Cholera ; On the Action of Bacteria on Various Gases ; A New Cortical Centre, by Graeme M. Hammond ; 

 The Unity of Nature, VII., by the Duke of Argyll ; Primitive Stages of Cosmical Evolution, by Prof. Alexandei 

 Winchell ; Books Received ; Correspondence; Notes, Astronomical, Chemical, Sc., &c, &c. 



Subscription, Four Dollars a Year, 



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