ST A 
etl ; lower reflexed at the sides ; the middle 
segments larger, emarginate ; stamens finally 
refiexed towards the sides. Tliere are 
twenty-tour species. 
ST^HELINA, in botany, so named 
from John Henry Stmhelin and liis son, 
Swiss physicians, a genus of the Syngenesia 
Polygamia Alqualis class and order. Natu- 
ral order of Coinpositae Discoidese. Cina- 
I'ocephalte, Jussieu. Essential character ; 
anthers tailed ; down branched ; receptacle 
with very short chaffs. There are ten spe- 
cies. 
STAFFA, an island situated on the coast 
of Scotland, three miles north-east of 
Iona, or Columb-kill, and west of Mull, 
about a mile in length, and half a mile in 
breadth, belonging to Mr. Laucblin Mac 
Quarie, This inconsiderable isle is one 
amongst the most wonderful productions of 
nature, and deserves the attention of every 
natural philosopher, though it is unfortu- 
nately placed in a region which prevents 
frequent visits, even from curious investi- 
gators. The peculiarity that renders it so 
interesting, arises from the basaltes compos- 
ing it, assuming a number of magnificent 
forms, equally astonishing and sublime , 
but as we purpose to describe them with 
some degree of minuteness, it will be pro- 
per to give a general sketch of the nature 
of the substance termed basaltes, and where 
it abounds, that the subject may be clearly 
understood. See Basaltes, 
According to Strabo and Agricola, the 
antique basaltes is found in the same pris- 
matical fonn in Egypt, which distinguishes 
its outline in various parts of Europe. 
Farber, a professor of natural history, at 
Mietau, supposes that found in the Vicentine 
Paduan and Veronese districts of Italy, to 
be a chrystallized lava, and asserts that the 
antique basaltes is in every respect exactly 
similar to the compact lavas of Vesuvius 
and Monte Alhano, which are used by sta- 
tuaries to restore mutilated statues made of 
this material. 
The Egyptian basaltes contain a small 
proportion in some of the varieties,, of the 
white garnet like shorl crystallizations, and 
lamellas common in the Italian lavas, a cir- 
cumstance that seems to (irove to deiiton- 
Stration their vqlcanic production in these 
particular instances, tltough others of the 
oriental basaltes seem to have originated 
from aqueous mixtures. 
Dr. Von Troil, member of the Academy 
of Sciences at Stockholm, entertained an 
opinion that they were caused by tlie ope- 
STA 
rations of fire, which he founded on that of 
M. Desmaret’s, who was the first naturalist 
that ventured to attribute them to that 
cause, in a description of some basalts found 
near St. Sandoar, in Auvergne, presented 
by him to the attention of the French Aca- 
demy of Sciences. Other naturalists who 
had considered them to be a species of 
chrystalhzation, ridiculed this idea as found- 
ed upon false principles, as they contend- 
ed basalt pillars are discovered where it 
seemed highly improbable that volcanoes 
could ever have existed ; still, however, 
they had the candour to enter into an ex- 
amination of the assertion of M. Desma- 
ret’s, the result of which was nearly a con- 
firmation of his conjecture, that basalt pil- 
lars were produced by subterraneous fires. 
As a collateral support of this hypothesis, 
Dr. Von Troil cites the instances of Stol- 
penstein in Meissen, Lauban in Lusatia, of 
Bohemia, Leignitz in Silesia, Brandau in 
Hessia, Sicily, Bolsenna, Montebello, and 
St. Forio in Italy ; the district of Vicenza, 
Monte Rosso in the district of Padua,, 
Monte Diavolo in the mountains of Vero- 
na, in Lower Languedoc, in Ireland, and 
in the western islands of Scotland, in each 
of which places he says a doubt cannot be 
entertained that volcanoes have existed ; 
besides those he mentions St. Giovanni, 
Monte Castillo, Monte Nuovo, Monte Oli- 
veta, near Cader Idris in Wales, and almost 
every part of Velay and Auvergne, where 
the towns of Chillac and St. Fluor are situ- 
ated upon basaltes. 
The peasantry of Iceland seem to have 
entertained a similar opinion of their origin 
to that of the lower orders of the Irish, as 
the former suppose them to have been piled 
in the regular manner, they are seen tliere, 
by giants, and thence call them Trollahland 
and Trollkonugardur, and the latter term 
their magnificent causeway, the Giants. 
The pillars of the Icelandic basaltes have 
generally from three to seven sides, they vary 
in thickness from four to six feet, aiid some 
are of thirty-six, and others even forty- 
eight feet in length, without horizontal divi- 
sions ; but such is the capricious operations 
of nature, that pillars are sometimes found 
not more than six or twelve inches long ; 
those, however, are invariably very regular, 
and are made use of for doors and win- 
dows ; at others they appear the utmost 
confusion, broken, and overturned ; in par- 
ticular instances tliey just appear above the 
surface of the mountains, amongst lava and 
tufa, and there are places vvhere they ex- 
