264 . Dr. Webster on St. Michael 
tinct loud explosions. occur at short» intervals, which are’ « 
sueceeded bya very. perceptible elevation of the bodys of : 
water within the basin... This is attended with’a loud: hiss~': 
ing; noise and the escape of great quantitiesof sulphuretted:» 
hydrogen gas; steam and sulphurous sacids vapour.” The : 
water of these springs is used in bathing houses ereeted near » 
them-and found highly beneficial in many:complaints. 9» 
‘Wherever the water has flowed, depositions of siliceous 
sinter have accumulated, and circular) basins; composed» 
entirely of this substance, have been here and there formed = 
round a spring. The siliceous:matter rises, in many places, 
eight or ten inches above the level of the water; and is of 
ten, exceedingly beautiful... Vegetables, grass, leaves and 
similar. substances which have been exposed to: the influ-'/ 
ence of the water are more or less incrusted with silex,: andz 
exhibit all the progressive steps of petrifaction ;. some being 
soft, and but little differing from their natural state ; while: 
others are partly converted into stone, or perfectly consoli+s 
dated.” .All these masses are more or less abundant im sul- 
phur, often crystallized and constituting splendid specimens. 
Much of the sinter resembles that of the geysersof lceland— » 
much. is represented as being far;more beautiful. One va~» 
riety, which has been described, in a former number of this} 
vol. Journal, pa. 26 is distinguished» by its structure and 
chemical composition (containing 16.35 per cent of | water)»: 
and Dr.W. proposes to designate it by the name ‘ Michael-« 
ite.” Silex occurs in the cavities of thesmassive sinter in 
stalactites, some of which are covered with ‘‘ small, brilliant 
erystals of quartz.”’ [on Ad 
Near the springs is'a remarkable breccia formed of frags 
ments of Java, pumice, sinter and obsidian, cemented by 
siliceous matter. From observing the ferruginous deposi- 
tionof some springs of cold water within.a few inches of 
the hot springs, and from the occurrence: of pebbles having 
a metallic stain; Dr. Webster suspected: the existence of 
sulphuretted iron and caused an extensive examination to 
be made. At a considerable depth below the surface, his 
conjecture was verified by “the discovery. of an abundance 
of sulphuretted-iron 3 a great quantity of which was thrown » 
up. Most.of the pieces were as large as aman’s head, with 
an irregular globular form.” These pieces had all the char-. 
acters of iron pyrites and in the author’s view, the existence 
