INDEX. 
S 
Sabine, Capt. his observations of signals at Lignieres, 85. 
, his observations of the pendulum discussed by Mr. 
Airy, 564. 
Sandius. Extract of a letter by, on the origin of pearls, 840. 
Savary, M. his observations of rocket signals from the observatory 
of Paris, 83. 
Saxicava rugosa , its mode of penetrating stones discussed, 362. 
Shell fish. Mr. Dyllwin on their mode-of burrowing and boring, 
342. 
Signals, sun’s reflexion used as, and how, 327 — a new species of 
light used for, 330 — instance of its application under difficult 
circumstances, 334. 
— , rocket. See Rochets. 
Signs used to express the action of machinery, 250. 
Slieve Snaght, signals from, observed at Divvis Hill, 334. 
Somerville, Mrs. M. on the magnetizing power of the sun’s rays, 
132. 
South, James, Esq. Observations of the positions and distances 
of 458 double stars, &c. &c. Part I. Vide the Index Catalogue 
at the end of Part I. 
, on the discordances of the sun’s observed and 
computed Right Ascension, and description of a seven-feet 
transit instrument, 423. 
Spatangus, its mode of burrowing, 347. 
Standard weights and measures, Capt. Kater on their adjust- 
ment, 1. 
Stars, fixed. Mr. Herschel on their parallax, 266. 
, list of, fit for observations for parallax, 277. 
double. See double Stars and the Index Catalogue at the 
end of Part I. 
Sulpho-naphthalic acid, its formation, 141 — purification, 146 — 
analysis, 156. 
Sulphonaphthalates , 148. 
Sulphovinates, Mr. Hennell’s experiments on, 245, &c. 
Sulphuric acid, its action on naphthaline, 140 — on alcohol, 244 — 
its saturating power diminished by union with hydrocarbon, 248 
— its perfect fixity at common temperatures, 489. 
Sun , magnetizing power of its rays, Mrs. Somerville on, 134. 
effect of on the braces of the Cambridge Transit, 74. 
magnetic influence in its rays, Mr. Christie on, 219. 
effect of its rays on Mr. South’s transit, 435. 
b 
mdcccxxvi. 
