146 INDEX. 



Numbers, developement of some curious properties in the powers 



of, V. 55 

 Nutation of stars, investigation of the correction of, viii. 21 

 Nutrition of plants, observations on, ii. 5. Of animals, 183 



Oak bark, substitute for, viii. 165 



Oatmeal, spontaneous combustion of, x. 454, 



Object-glass (triple), remarks on the concentric adjustment of, 

 xiv. 163 



Observatory, new astronomical, at the Cape of Good Hope, ix. 391 



Ocean, hypothesis to account for the variable depth of, vi. 226 



— elevation of, xiii. 230 



Occultations (lunar), table of the places of certain stars that are 



liable to, x. 145. Table of the logarithms of the corrections in 



seconds, to be applied with the proper signs of the series, 148. 



For the different places of the moon's node, 152. Computation 



. for a visible occultation, 161 



< ■ ■ rules for computing, xviii. 343 



Odier (Dr.), bibliographical notice of, iii. 418 



Odours, theory of the origin of, x. 1 16 



(Edipus expounding the enigma of the Sphinx, description of an 

 ancient gem representing, xii. 1 1 



Oersted (M.), observations of, on Schweigger's electro-magnetic 

 multiplier, xvi. 123. Experiments of, on thermo-electric mag- 

 netism, 126. Account of his experiments with the magnetic 

 needle, 342 



' experiments of, on accelerating distillation, xix. 142 



Ohio (state), first settlement of, iii. 81. Soil and produce, 82. 

 Population, ib. Geological structure of, 83 



(river), description of the cat-fishes found in, ix. 48 



Oil, production of gas from, vi. 108. yii, 313. 



— gas, advantages of, over that from coal, vii. 313. viii. 120. 

 xiii. 423. 



— obtained from pumkins, vii. 370 



— painting, purple colour for, viii. 38, 38 



— of wheat, remarks on, iii, 417. 



