INDEX IIs 905 
climates, 188; on the application of 
telescope sights to rifles, 188. 
Soap-test, on the action of the, upon 
water containing a salt of magnesia 
only, and likewise upon water contain- 
' ing a salt of magnesia and a salt of 
lime, 49. 
Solids, on the laws of the elasticity of, 
2;.on the expansion of, by heat, 16. 
Sorby (Henry Clifton) on the tetramor- 
phism of carbon, 62. 
Soukaneeah dialect of the Berber, 142. 
South America, on earthquakes in, from 
1844-47, 82. 
Space, on a physiological mode of resol- 
ving the metaphysical difficulties as to 
the origin of the notion of, 135. 
Spain, notice on the geological structure 
of, to explain an outline general map 
of the Peninsula, 108. 
Speculum, on a method of supporting a 
large, free from. sensible flexure, in all 
positions, 180. 
Spleen, on the supposed relation of the, 
to the origin of the coloured blood-cor- 
puscle in the adult, 134. 
Stars forming binary or multiple groups, 
on the alleged evidence for a physical 
connexion between, 23. 
Statistics, 147. 
Steam-engines, on the incrustation which 
forms in the boilers of, 51. 
Steam vessels, on improvements in pro- 
pelling and navigating, 186. 
Stein (James) ona direct method of sepa- 
rating arsenious from arsenic acid, and 
On its application to the estimation of 
nitric acid, 62. 
Stenops, on the genus Perodicticus of 
Bennett, and its relation to, 125. 
Stevelly (Prof.) on the occasional distinct 
vision of rapidly revolving coloured 
sectors, 21. 
Stevenson (Thomas) on the force of the 
“waves, 189. 
Stokes (Prof.) on the mode of disappear- 
ance of Newton’s rings-in passing the 
angle of total internal reflexion, 19; on 
metallic reflexion, ἐδ. ; on Haidinger’s 
brushes, 20; on a fictitious displace- 
ment of fringes of interference, ib. 
Storms, on the passage of, across the 
British Islands, 42. 
Stove, gas, 191. 
Strachey (Lieut.) on hourly meteorologi- 
- cal observations made in Thibet at an 
elevation of 18,400 feet, 43. 
Strang (John) on the progress of Glas- 
gow, in population, wealth, manufac- 
tures, &c., 162. 
Strata, on the succession of, in the Dor- 
setshire purbecks, 79. 
Strickland (H. E.) on a peculiar structure 
in the submedial pair of rectrices of 
Vidua paradisea, 126. 
Substance, on a physiological mode of 
resolving the metaphysical difficulties 
as to the origin of the notion of, 135. 
Sugar produce of the south of Spain, on 
the, 60. 
Sunlight, on the influence of, over the 
action of the dry gases on organic co- 
lours, 65. 
Swan (William) on the limits to the ve- 
locity of revolving lighthouse appara- 
tus caused by the time required for the 
production of luminous impressions on 
the eye, 191. 
Switzerland, parallel between the super- 
ficial deposits of the basin of, and those 
of the valley of the Po in Piedmont, 90. 
Sykes (Lieut.-Col.) on Indian hail-storms, 
43; statistics of criminal and civil jus- 
tice under the Bombay Government 
for the years 1844-47, 159. 
Taylor (Henry) on the chemical composi- 
tion of the rocks of the coal formation, 
63. 
Tessellated pavements discovered at Ci- 
rencester, on some chemical facts con- 
nected with the, 48. 
Thermometrical maxima at or near the 
moon’s first quarter during the years 
1839-50, 32. 
Thibet at an elevation of 18,400 feet, on 
hourly meteorological observations 
made in, 43. 
Thomson (Prof. W.) on the theory of 
magnetic induction in crystalline sub- 
stances, 23. 
Thomson (W.) on the dentition of the 
British pulmoniferous mollusca, 126. 
Thomson (Wyville T. C.) on the applica- 
tion of photography to the compound 
microscope, 126. 
Tilt (Dr. E. J.) on the causes which ad- 
vance or retard the appearance of first 
menstruation in woman, with a synop- 
tical table showing the mean age of first 
menstruation in 10,422 women in hot, 
temperate, and cold climates, 135. 
Tyndall (John) on the magneto-optical 
properties of crystals, 23. 
United Kingdom, on the expediency of 
ascertaining the extent to which idiocy 
prevails in the, 128. 
Valves, improvements in, for regulating 
