INDEX. 



1051 



Rumford medals, awarded to M. Faraday, 

 635 ; V. Regnault, 773 ; F. J. D. Arago, 

 1011. 



Sabine (Lieut.-Col.), contributions to ter- 

 restrial magnetism, No. VI., 507 ; No. 

 VIL, 622. 



— — , on the lunar atmospheric tide at 

 St. Helena, 663. 



— — , on the diurnal variation of the 

 magnetic declination of St. Helena, 664. 



, remarks on M. De la Rive's theory 



for the physical explanation of the 

 causes which produce the diurnal vari- 

 ation of the magnetic declination, 821. 



, memoir to accompany a map of the 



magnetic variation, for 1840, in the 

 Atlantic Ocean, between the parallels 

 of 60° N. and 60° S. latitude, 835, 

 No. IX. 



, Royal medal awarded to, 871. 



— — , on the means adopted in the Bri- 

 tish colonial magnetic observatories for 

 determining the absolute values, secu- 

 lar change, and annual variation of the 

 magnetic force, 942. 



Safety -lamp, presented to the Society by 

 J. Hodgson, Esq., particulars of, 950. 



Salts, binary composition of, 504 ; double, 

 the two ions of the electrolyte evolved 

 from, 505. 



— — , various diffusibility of, 898. 



Sap, observations and experiments on the 

 cause of ascent and motion of, 502. 



Saussure (T. de), obituary notice of, 

 583. 



Savage (T. S.), account of the desquama- 

 tion and change of colour in a negro 

 of Upper Guinea, West Africa, 623. 



Schoenbein (C. F.) on the production of 

 ozone by chemical means, 507, 508, 

 565. 



— -— on a new bleaching principle pro- 

 duced by the slow combustion of ether 

 in atmospheric air, and by the rapid 

 combustion of bodies in a jet of hydi-o- 

 gen gas, 543. 



■ on spontaneous nitrification, 601. 



Schwann (T.), Coplev medal awarded to, 

 576. 



Sea, remarkably large and luminous spot 

 in, 475. 



, sudden rise and fall of, 495. 



— « — , extraordinary oscillations of ; elec- 

 tric discharges the presumed cause of, 

 962. 



, on the caUing of, 968. 



water, analysis of, 476. 



Secondary compounds, electrolysis of, 504. 

 Sextant, protracting, account of, 563. 

 Sharp (W.) on the ashes of wheat, 554. 



Ships, speed of, registered by column of 

 mercury, 919. 



, superiority of iron for, 961. 



Shortrede (R.), essays on hygrometry and 

 barometry, 548. 



— — ■ , on a formula for the elastic force of 

 vapour at different temperatures, 738. 



, on the moist-bulb problem, 740. 



Sibson (F.) on the mechanism of respira- 

 tion, 601 ; on the blowhole of the por- 

 poise, 604. 



Simon (J.) on the comparative anatomy 

 of the thjToid gland, 515. 



Sirius and Procyon, observations on, 1005. 



Smith (J. A.), suggestion intended to 

 confirm Franklin's theory of electro- 

 statics, by explaining the phenomena 

 of repulsion between bodies negatively 

 electric, 630. 



Smith (R.) on the decomposition and 

 analysis of the compounds of ammonia 

 and cyanogen, 599. 



■ on the aurora borealis which oc- 

 curred in November 1848, 790. 



Smyth (C. P.), attempt to apply instru- 

 mental measurement to the zodiacal 

 light, 761. 



Smythies (J. K.) on the universal law of 

 attraction, incitiding that of gravitation, 

 as a particular case of approximation 

 deducible from the principle that equal 

 and similar particles of matter move 

 similarly, relatively to each other, 831. 



Snow, a result of meteoric phenomena, 

 811. 



Soda, phosphate of, more abundant in 



arterial than in venous blood, 677. 

 Soil, inorganic matters abstracted from, 



by plants, 551. 

 Solar radiation, different properties of, on 



silver plates coated with iodine, &c., 



679. 



spectrum, endowed with three dif- 

 ferent photogenic actions, 681. 



system, proper motion of, 670. 



Solutions, magnetic condition of, 593. 



Somerville on the action of the rays 

 of the spectrum on vegetable juices, 

 569. 



Soimd, emitted by the luminous voltaic 



arc when under magnetic influence ; 



substances which produce it, 660. 

 South America, astronomical observations 



proposed to be made in, 768. 

 Specific gravities, new table of, 682. 

 Specti'um, solar, focus of photogenic rays 



in, 513; theory of certain bands seen 



in, 794. 



Speculum, extraordinary, weight and di- 

 mensions of ; power of, 963 ; strain and 

 flexure of ; supports of, 964. 



8* 



