LAKES IN KELATION TO GEOLOGICAL FEATURES 511 
Spynie. — Shallow lake in raised beach deposits, and probably ponded by 
the westward-travelling beach which deflects the Lossie westward 
to Lossiemouth. It was connected with the sea within historic 
times. 
Sreinge^ na. — Rock-basin in schists, limestone, and epidiorite. One side 
of the lake is traversed by a line of fault along which successive 
intrusions of basic and acid dykes have been injected and small 
volcanic vents have been drilled in Tertiary time, 
Sron Smeur. — Rock-basin in granite. 
Staca, an. — Ponded by drift. It lies on the watershed of the high 
plateau between the rivers Morriston and Enrick (Glen Urquhart). 
Stack. — Rock basin in Lewisian Gneiss. It encloses two parallel basins 
along separate bands of gneiss and foliated granite. The main rock- 
basin is probably continuous through Loch na h-Ealaidh to Loch 
More. Loch Stack was formerly much more extensive, as it is 
surrounded by high terraces of alluvium which are continued down 
the Laxford for over two miles below the present outlet, and up as 
far as Loch na h-Ealaidh (see Loch More). 
Stacsavat — Rock-basin in Lewisian Gneiss. 
Stainge, na.— Ponded by moraines. 
Stenness. — Tidal loch, only fresh at surface, partly ponded by drift, which 
probably lies in a rock-basin in the Middle Old Red flagstones. It 
is separated from Loch H array by a shallow channel with rocky floor 
over M'hich the salt water sometimes flows out of Loch Stenness into 
Loch Harray. 
Strandavat. — Hollow in Lewisian Gneiss. 
Strom. — Rock-basin along strike of crystalline schists ; a tidal loch. 
Strumore, an. — Tidal loch. 
Suainaval. — Valley rock-basin in Lewisian Gneiss. 
Swannay. — Ponded by drift resting on Middle Old Red flagstones. 
Syre. — Shallow, irregular lake in moraine drift. 
Tachdaidh, an. — Vol. II. Part I. p. 353. 
Tairbeirt Stuadhaich, an. — Rock-basin in Lewisian Gneiss. 
Talla. — Artificial reservoir in valley excavated in Silurian greywackes 
and shales. The floor of the valley is covered by boulder clay and 
alluvium. 
Tankerness. — In drift which rests upon Middle Old Red flagstones. 
Tarruin an Eithir — Rock-basin in I^ewisian Gneiss. 
Tay.— Vol. II. Part I. p. 138. 
Tearnait. — Partly in schists and partly in drift. 
Thom. — Artificial reservoir probably on site of smaller loch, in Lower 
Carboniferous rocks of the Renfrewshire plateau. 
Threipmuir. — Artificial reservoir in forking valley carved out of Lower 
Carboniferous and LTpper Old Red Sandstone strata partly covered 
by boulder clay. 
Tilt. — Partly a rock-basin along the line of the Glen Tilt shatter-belt. 
