INDEX. 



757 



Page. 



Nitrogen, loss of, in agriculture 



Noble, W., on Indian rain making ^^^ 



Nollner on nitrate deposits 



Nordenskiold, Baron, subscription by ^^^ 



Nordenskj old's globe 



North American Ethnology, appropriation for xxxviii, 4 



receipts and expenditures xviii 



report on 28, 44 



North German Lloyd, courtesies from 65 



Norway, exchange agency J 



transmissions to. bb, b7 



51 

 Nouri, Dr. J.J 



Noyes, Isaac P., on rain makers -'" 



Number systems, primitive 



Nutation, constants of 101,10^ 



C). 



Obarrio, Melchor. courtesies from ^^ 



Observatory on Mont Blanc -'^^ 



Ocean, bottom, characteristics of ^^ 



jjrimitive fauna of - - - ^ ' ^ 



discovery of, Professor Brooks on _ 359 



currents and food supply ^^ 



Wharton on ^^"^ 



depth of, Wharton on- '^^^'3^! 



mean level of - - - ' 



physical condition of, Wharton on -- 34d 



tidal waves on 



waves caused by earthquakes ^ ^^i.- 



O'Dell, L. N. , donation to Zoological Park '^3' ^3 



Odogenesis, definition of - - 



Odograph, for measuring steps - - ^ - - - - 



Oelrichs& Co., courtesies from. ' ^ 



Oersted, electrical discoveries by ^^^' 



■ • 4-Yo 4y4 



Oertel, on muscle training ' 



Ohlin, Dr., Arctic exploration by °^ 



Ohm, George Simon, scientific work of ^3 



sketch of life of --- i*^ 



Ohm, electrical unit of resistance.. - ^J^ 



Ohm's law in electricity \qi 



Okhotsk Sea, food supply in 



Olney, Richard, member of Smithsonian Institution ix, 1 



Ommanney, Admiral Sir Erasmus ^^^ 



Opthalmometer , invention of 



Ophthalmoscope, invention of .-- ' 



Optical deflection of straight lines ^ ' 



effects of curves 



Optics, Helmholtz's researches in - ' 



Organic evolution, method of 



stability. - - 



Organism, subordination of parts of 



Oriental discoveries by Layard 



