ME. J". MARTIN OX THE TEEEACES OE E0T0MAHAXA. 



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dants, from which the overflow trickled in a glistening shower. 

 This was the most conspicuous portion of the whole structure, the 

 gradual descent of the formation on either side leaving the centre 

 overhanging more than twelve feet above a basin which beautifully 

 reflected its curious architecture. 



This natural division was also marked by a level path varying in 

 width from 2 to 20 feet, which extended right across the face of the 

 Terrace from east to west, broken only by a few steps near the 

 centre. 



Upon this belt, and almost exactly in the centre of the Terrace, 

 was the rough protruding rock known from its peculiar shape as the 

 Boar's Head. 



A little further towards the east was the Broken Basin, a circular 

 pool 12 feet in diameter, about 26 inches deep, of similar height 

 upon its outer front, the only warm-water basin on the White 

 Terrace deep enough to be used as a bath ; its temperature varied, 

 according to the overflow, from 120° to 90°, its interior surface was 

 rough like concrete, and a sedimentary deposit was disturbed when 

 bathing. Some time ago an opening must have been roughly hewn 

 out of the rim, forming a depressed lip about 12 inches across and 4 

 inches deep, through which the overflow poured into another shallow 

 basin below. 



The deposition of sinter here must have been very slow, as 

 scratches and markings made in the hollow of the broken lip two 

 years since were barely covered by a thin glaze. 



The Middle Terrace. 



The central portion of this part of the structure was distinguished 

 by a series of massive, rugged, and rippled perpendicular elevations, 

 mairy of which exceeded six feet in height ; some were decorated 

 with pendent wool-like fringes, some with deeply engraved parallel 

 lines, and others with small upturned scales. The central ones were 

 approached on either side by lower ridges, which together formed an 

 ascent of about two hundred steps. At increasing distances ■ from 

 the centre, these elevations were again and again reduced until, 

 near the margin, they merged into wide incrusted slopes marked by 

 lines of interlacing ripples which formed protecting ridges less than 

 half an inch in height. 



These elevations, although presenting the characteristic lines of 

 level surface, formed compact platforms, tables, or steps — only one 

 depression occurring in the whole series, and that but a small muddy 

 pool. 



Although the normal overflow covered the whole of the Terrace, 

 any diminution in quantity left many of these central masses dry. 

 The deposition of silica appeared to be scarcely sufficient to preserve 

 the compact character of the surface, and those parts most exposed 

 to the action of the atmosphere were disintegrating and becoming 

 loose and fragmentary. 



It seems but reasonable to suppose that these central elevations 



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