512 THE FRESH-WATER LOCHS OF SCOTLAND 
The loch is in a through valley between the Tilt and the 
upper Dee, 
TiNGWALL. — -Rock-basin lying along the strike of crystalline schists and 
metamorphic limestones. 
ToLLiE.— Vol. n. Part L p. 240. 
ToMAiN, AN. — Irregular rock-basin in Lewisian Gneiss, studded with 
islands (rockes 7noutoJi?ices). 
ToRMASAD. — Rock-basin in Lewisian Gneiss. 
Tralaig, — Rock-basin in schists and epidiorite^ with volcanic rocks of 
Lorne plateau on each side. 
Trealaval. — Irregular, shallow loch, probably a rock-basin in part, 
lying in Lewisian Gneiss. 
Treig.— Rock-basin in schists along the Loch Leven and Loch Etive 
shatter-belts. It lies in a valley open at both ends, which has been 
one of the outlets from the Rannoch Moor ice-cauldron. 
Trool. —Rock-basin in Lower Silurian greywackes, situated in one of 
the valleys draining the Galloway ice-cauldron. 
Truid AIR Sgithiche. — Hollow in drift. 
TuiRC, AN.— Vol. II. Part I. p. 188. 
Tulla. — Rock-basin in Moine schist, partly along Loch Laidon shatter- 
belt. The lake occupies one of the outlet passes from the Moor 
of Rannoch ice-cauldron, the Orchy having pirated the upper 
tributaries of the Tay in pre-glacial time. During the retreat of 
the later glaciers, the outlet valley must have been blocked by 
ice from the high ground to the west, as there are two terraces 
of silt which extend far up the valley of the Tulla above the 
lake. Loch Tulla has been silted up to some extent by tributary 
streams. 
TuMMEL.— Vol. IL Part 1. p. 137. 
Turret. — Rock-basin in schistose grits, partly ponded by moraines. 
TuTACH. — Kettle-hole in fluvio-glacial deposits. 
Uanagan. — Small rock-basin in shatter-belt of Great Glen. 
Urigill.— Vol. II. Part I. p. 191. 
Urr. — Partly in Silurian greywackes and partly ponded by drift. 
Urrahag. — Rock-basin in Lewisian Gneiss. 
UssiE.— Vol. II. Part I. p. 290. 
Vaara. — Partly a rock-basin in altered Old Red Sandstone strata and 
intrusive igneous rocks, and partly drift-dammed. 
Valtos. — Irregular rock-basin in Lewisian Gneiss. 
Vatandip. — Rock-basin in Lewisian Gneiss. 
Veiragvat. — Rock-basin in Lewisian Gneiss. 
Vennachar. — Vol. II. Part I. p. 49. 
Veyatie.— Vol II. Part I. p. 188. 
VoiL.— Vol. II. Part I. p. 45. 
Vullan, a'. — Hollow in glacial deposits. 
Watten. — Shallow loch ponded by boulder clay in wide open valley. 
