ution of Great Britain on the 25th of May 1906; "Diving and Caisson
Disease," a summary of recent investigations, by Surgeon Howard Mummery,
_British Medical Journal_, June 27th, 1908; _Diseases of Occupation_, by T.
Oliver (1908); _Diseases of Workmen_, by T. Luson and R. Hyde (1908).

CAITHNESS, a county occupying the extreme north-east of Scotland, bounded
W. and S. by Sutherlandshire, E. by the North Sea, and N. by the Pentland
Firth. Its area is 446,017 acres, or nearly 697 sq. m. The surface
generally is flat and tame, consisting for the most part of barren moors,
almost destitute of trees. It presents a gradual slope from the north and
east up to the heights in the south and west, where the chief mountains are
Morven (2313 ft.), Scaraben (2054 ft.) and Maiden Pap (1587 ft.). The
principal rivers are the Thurso ("Thor's River"), which, rising in Cnoc
Crom Uillt (1199 ft.) near the Sutherlandshire border, pursues a winding
course till it reaches the sea in Thurso Bay; the Forss, which, emerging
from Loch Shurrery, follows a generally northward direction and enters the
sea at Crosskirk, a fine cascade about a mile from its mouth giving the
river its name (_fors_, Scandinavian, "waterfall;" in English the form is
_force_); and Wick Water, which, draining Loch Watten, flows into the sea
at Wick. There are many other smaller streams well stocked with fish.
Indeed, the county offers fine sport for rod and gun. The lochs are
numerous, the largest being Loch Watten, 23/4 m. by 3/4 m., and Loch Calder, 21/4
by 1 m., and Lochs Colam, Hempriggs, Heilen, Ruard, Scarmclate, St John's,
Toftingale and Wester. So much of the land is low-lying and boggy that
there are no glens, except in the mountainous south-west, although towards
the centre of the county are Strathmore and Strathbeg (the great and little
valleys). Most of the coast-line is precipitous and inhospitable,
particularly at the headlands of the Ord, Noss, Skirsa, Duncansbay, St
John's Point, Dunnet Head (346 ft.), the most northerly point of Scotland,
Holburn and Brims Ness. From Berriedale at frequent intervals round the
coast occur superb "stacks," or detached pillars of red sandstone, which
add much to the grandeur of the cliff scenery.

Caithness is separated from the Orkneys by the Pentland Firth, a strait
about 14 miles long and from 6 to 8 miles broad. Owing to the rush of the
tide, navigation is difficult, and, in rough weather, dangerous. The tidal
wave races