STA 
fegwlai'ity obserirable in its texture. On 
passing further, and on the south-east side of 
the island, the basalt columnar appearance 
commences, though almost imperceptibly ; 
hence they gradually assume their charac- 
teristic form, till at last the spectator finds 
himself on the spot where they are in full 
perfection. 
The shape of the columns vary from 
three to seven sides, though the majority 
have five and six ; the former are so numer- 
ous, that a heptagonal pillar is surrounded 
with seven others, which join closely to its 
seven sides. In some instances inconsider- 
able fissures may be perceived, but those 
are generally filled with quartz, and in one 
particular place that had penetrated fftroUgh 
several pillars without interrupting, the re- 
gularity of their arrangement, one of the 
greatest wonders attending this operation 
of nature, is the separation of each pillar 
into pieces, which are so closely jointed, 
that it is almost impossible to introduce a 
knife between the interstices. Upon an 
attentive examination of many of those 
pieces, it was found that the uppermost 
was generally concave, in some cases flat, 
but very rarely convex. When the upper 
surface was flat, the lowest joint was the 
same; but when it was excavated, the 
lower one was rounded and reversed. 
The sides of the pillars are of unequal 
dimensions, to prove which we shall give 
the measurement of two, extracted from 
the Letters on Iceland, containing Dr. Von 
TroH’s communication on this subject. 
One with four sides. , 
Ft. In. 
First side 1 5 
Second 1 1 
Third 1 6 
Fourth - 1 1 
With seven sides. 
Ft. In. 
First side 2 10 
Second 2 4 
Third 1 10 
Fourth 2 0 
Fifth 1 1 
Sixth 1 6 
Seventh 1 3 
The angles are as sharp and well defined 
^s those of the pillars of the Giant’s Cause- 
way in Ireland, and their colour is gene- 
rally black, the inclination to yellow being 
confined to the external sides, which are 
exposed to, and in some degree bleached 
STA 
by the action of the sun, rain, and wind. 
The texture of their substance much resem- 
bles, and is probably the same as the Ice-' 
landic agate. Professor Bergman was di- 
vided in opinion, whether these pillars were 
produced by fire acting upon particular 
substances, or whether subterraneous fires, 
sending forth vapour, may have softened 
the superincumbent earth, which becoming 
soft, and yielding to the force below, as- 
cended in this peculiar form, and became 
gradually petrified. This latter supposition 
met the ideas of Von Troil, who illustrates 
it by saying, he has observed the distinct 
and regular appearance alluded to in dried 
clay, and even starch, when dried in a ba- 
son. “ For,” adds the latter, “ it may be 
demonstrated that they are not crystals 
formed by nature, by their not being pro- 
duced as all other crystals are, by external 
apposition (per appositionem), nor in any 
other matrix, as is common among crys- 
tals.” He further observes, “ The follow- 
ing may, however, serve as a proof that I 
did not, without due foundation, believe 
them to be a kind of lava, which burst in 
growing cold and hard. First, you find 
both in the Island ofStaffa, and many other 
places, that the pillars stand on lava or 
tufa, and are surrounded by this matter. 
Secondly, at StafFa there was a large stra- 
tum above the pillars, in which there were 
many pieces of those pillars irregularly 
thrown one among another, which leaves us 
to conjecture that they must have been more 
in number, and higher, after an old erup- 
tion of fire ; but that a subsequent eruption 
had overthrown them and mixed them with 
the whole mass.” 
STAIR-CASE, in architecture, an as- 
cent inelosed between walls, or a balus- 
trade, consisting of stairs, or steps, with 
landing-places and rails, serving to make a 
communication between the several stories 
of a house. The construction of a com- 
plete stair-case is one of the most curious 
works in architecture. 
STAKE, the name of a small anvil, used 
by smiths ; sometimes it stands on a broad 
iron foot on the work-bench, to be moved 
up and down occasionally ; and sometimes 
it hath a strong iron spike at the bottom, by 
which it is fixed to some place on the work- 
bench. Its use is to set small and cold 
work straight, by hammering it on the 
stake ; or to cut or punch upon the cold 
chissel or cold punch. 
STALACTITiE, stony icicles, in natural 
history, crystalline spars formed into ob- 
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