394 PROCEEDINGS OF SECTION B. 
the boiling spring on the shores of a lagoon (very probably an 
old crater) on the south-west side of the island.. The spring is 
placed amongst decomposed trachytic rocks, a foot or two above 
the sea level. Its temperature is 212°, and large quantities of 
HS are exhaled. Iron oxide stains the rocks around, which are 
encrusted with sulphur and chloride of sodium in some places. 
Numerous fumaroles pierce the slopes overlooking the springs : 
sulphur, alum, milk-white opal, &c., form deposits around their 
orifices. As this spring is close to the edge of the lagoon of salt 
water, with the tidal movements of which its waters rise and 
fall, I am of opinion, from a cursory examination of the water, 
that its compositiom may be regarded as sea water, plus the 
substances discharged by a fumarole. 
Bottle 150.—Water condensed from one of the fumaroles in the 
solfatara on the south-west point of Simbo, in May, 1882. A 
little sulphur, which unavoidably fell in, forms a sediment at the 
bottom of the bottle. For two hours the thermometer retained in 
the orifice of the fumarole varied only between 208° and 210° F. 
Watery vapour, sulphuretted hydrogen, and sulphurous acid were 
evolved, flaky crystals of sulphur enérusting the sides of the 
aperture. A strip of paper, soaked in a solution of acetate of 
lead, was immediately blackened, and the black metallic silver 
sulphide was formed in the interior of a piece of glass-tubing, 
moistened with silver nitrate, whilst the presence of sulphurous 
acid appeared to be indicated by the suffocating smell of burning 
sulphur, by the presence of sulphur deposits, and by the reddening 
of litmus paper. No turbidity was produced in lime-water, nor 
was the presence of hydrochloric acid gas shown on exposing a 
solution of silver nitrate. 
The interior of the solfatara was whitened by the decomposing 
influence of the vapours evolved. The elevation of the fumarole 
in question was rather under 300 feet above the sea. 
Bottle 151.—Water condensed May, 1882, from one of the 
fumaroles on the summit of the South Hill, in the island of 
Simbo, elevated about 1100 feet above the sea. The temperature 
of the fumarole varied during two hours between 175° and 180° F. 
Employing the same rough field tests, I ascertained that watery 
vapour was the principal substance discharged. No effect was. 
produced on acetate of lead, silver nitrate, or lime-water, and 
litmus paper was very slightly reddened after a prolonged 
exposure. No deposits were formed around the orifices of the 
fumaroles on this hill summit. The trachytic rock was much 
decomposed, and a little of the decomposed rock unavoidably fell 
in, and forms a sediment at the bottom of the bottle. 
For an additional example of water from hot springs at Suva, 
Fiji, see “ At Home in Fiji,” by F. M. Gordon Cumming. 
