THE bright morning had the promise of a hot day ahead as

I bailed out some overnight rain from the dinghy. We were anchored in Clach Chuirr (Port Ruadh) in the Sound of Gunna. There was a splash and two large dolphins surfaced within an arm's reach of me. They seemed amused by my efforts and for the next half-hour they played hide-and-seek, showing their white undersides in the clear water as they slipped under the dinghy or beneath Jandara's keel.

Later they returned to accompany us across the sound to the low-lying island of Gunna. Adrian de Ferranti, whose brother Marcus is the owner, told us that the two friendly dolphins have been resident for the past six or seven years and love to greet boats as they sail by.

Gunna is one of our many Scottish islands which is little known and usually ignored. It is narrow and wind-blown, no more than 500m wide for most of its length and fewer than 170 acres in area. It lies between Coll and Tiree. A humpy bedrock of paragneiss schist is covered with a light soil and there are few prominent features except for a beautiful beach of clean Hebridean sand which partly surrounds the anchorage. The owner grazes about 18 semi-wild cattle which swim over to Coll whenever the word ''abattoir'' is mentioned in their presence, but the island grass is mainly cropped by large numbers of barnacle, white-fronted and greylag geese which bed-and-breakfast here. Their chipolata-shaped droppings are everywhere. Gulls and terns nest on

the island but as it is such a short swim from Coll brown rats are reputed to mount occasional egg-raids. Shelduck are prolific in the spring.

We dropped anchor in the small bay on the west side of Eilean nan Gamhna, which is a tiny islet connected to Gunna at low water. The water was crystal clear and every link of the chain could be seen as the anchor dug in to the clean sand bottom. The area in the immediate vicinity of Gunna is peppered with rocks and there are more rocky patches off the Tiree shore but most of the rocks can be easily identified whatever the state of the tide.

Harry and Ronald explored the far side of the island while I walked across the tussocky grass to reconnoitre Port na Cille (port of the chapel or cell).

This is a rocky inlet with a small square ruin which may have originally been

the ''cille''. Latterly it was more likely

to have been used as a small but superior-quality sheiling. It is beside a fresh-water spring which was dry due to the recent prolonged spell of dry weather. There are also other signs of summer sheilings but there is no official record of Gunna ever having been permanently inhabited.

A level depression in the centre of the island - sheltered from the wind - could have been cultivated at one time and a distinctive cave in the centre of the north coast may once have served as

an anchorite's shelter. The island

was probably named after someone called Gunni as this was a common Danish name.

From the highest point which is only just over a hundred feet above sea level it is possible to look across the sound and see the entire spread of low-lying Tiree while to the south-west the distinctive volcanic shape of Bac Mor, better known as the Dutchman's Cap, looks like a battleship bearing down on Iona. On my way back to the beach I met a botanist holding a clipboard on which she was noting and classifying the many varied species of wildflowers, grasses and mosses which grow in this lovely unspoilt environment.

After our walk in the hot sun we swam lazily in the shallows where the water was as warm as a South Sea lagoon before returning to the boat for a welcome 'sundowner'.

l Hamish Haswell-Smith's book, The Scottish Islands (ISBN 0 86241 579 9), is published by Canongate at #25. Herald readers can obtain the book at the special price of #20 including p&p. Phone with credit card details to 0131 557 5111, or send a cheque, made payable to Canongate Books, to 14 High Street, Edinburgh EH1 1TE.