By HAMISH HASWELL-SMITH

It's like mining for precious stones. Dig deep enough, and every now and again another interesting piece of information turns up about one of our tiny little bits of land scattered around Scotland. For instance, I only discovered fairly recently that, in 1941, on a cold wartime Hogmanay, a Sergeant Makin was flying a Gloster Gladiator over Yell Sound in Shetland when the engine cut out. He calmly landed his plane on boggy ground on Samphrey Island where it somersaulted and settled upside down. He climbed out unhurt. He had known exactly what to do because about a year before he had executed exactly the same manoeuvre and achieved the same result. And, for all I know, he repeated the act for a third time.

When I was researching for the first edition of my book on the Scottish islands, I was faced with the difficulty that there was no list of all our islands. This is understandable because there was no clear definition of exactly what constituted an island in the first place. And for the same reason there was no consistent record of the sizes of our islands. So, after deciding on a definition, I set about measuring the area of every little piece of splintered land that I could find - a very long and laborious task - but it did eventually allow me to draw up a logical catalogue of everything which could be called an island. There is, of course, no true limit to the number of these because, after all, every rock or pebble sticking out of the sea could be called an island. So I set, quite arbitrarily, a minimum size of 40 hectares or about 100 acres. I felt this was manageable.

That was all right for the islands themselves, but what about all the other little bits and pieces which I think of as islets? Some of these have had their brief moment of historical interest or infamy. Some hide a secret, some display a dramatic topological feature, some are of extraordinary beauty. It's the excitement of the chase. What further gems of information can one uncover?

LITTLE ROSS

Guarding Kirkcudbright Bay in the Solway Firth, a pleasant little islet with an automated lighthouse is a scene of tranquility. Nowadays, It houses two families in the converted lighthouse-keepers' cottages. Only the rhythmic whisper of the sea and the cries of seabirds disturb the peace. But for many centuries Little Ross was a home for smugglers.

In August 1960, when the usual lighthouse keepers were on holiday, Hugh Clark, a 64-year-old retired postman from Dalry, stood in as relief keeper. His assistant was a 24-year-old sailor called Robert Dickson. During one gentle summer's day that month, the local bank manager, TR Collin, was out sailing in his dinghy near Little Ross. Collin had his 19-year-old son, David, along with him. It was midday, so they moored and went ashore to have a picnic lunch and take a stroll across the island.

As they approached one of the cottages, the Collins heard a telephone ringing continuously. They were surprised that no-one was answering and there was no sign of the keepers, so Mr Collin knocked on the door. After a time, getting no reply, he opened the door and they entered the house.

Mr Clark was dead. He was lying on a blood-soaked bed with serious injuries to his head and there was no sign of his assistant. So the Collins sailed back to the mainland and rang the police.

After several hours the police and a doctor were taken to the island on a launch piloted by a local fisherman. It was an obvious case of homicide and it was later established that death was due to rifle shots to the head.

The police put out a notice that they wished to interview the assistant keeper, Robert Dickson, and that they were trying to trace his car - a fairly old grey Wolseley. The car was normally parked at Ross Farm, which was on the mainland at the closest point to Little Ross. In due course, the car was found abandoned in Dumfries and, after a nationwide hunt, Dickson was arrested in Selby, Yorkshire.

Dickson was charged with the murder of Hugh Clark and stood trial in Dumfries High Court. He was found guilty. The defence had pleaded that it could not be truly called murder as Dickson had a "Jekyll and Hyde character". Dickson never said what drove him to murder his fellow keeper. But he told his mother, cryptically, that it was "God's law - an eye for an eye and a tooth for a tooth". Today, it would have been recognised that he was clearly mentally unbalanced. A storm raged outside the courtroom when Lord Cameron donned the black cap and delivered the death sentence: "...to be hanged by the neck until you are dead on the 21st December 1960 between 8 am and 10 am".

However, on the 16th December, five days before the execution, Robert Dickson had his sentence commuted to life imprisonment. It was of little consequence. He later committed suicide.

HAISGEIR MHOR

When sailing from the Sound of Harris to St Kilda the small Haskeir, or Haisgeir, archipelago can be seen to the south. The Gaelic, or Norse-Gaelic, names of the two largest islets are Haisgéir Mhor and Haisgéir Eagach. Their names mean, respectively, the Great Deep-Sea Skerry and the Notched Deep-Sea Skerry. There are any number of spellings for these Norse-Gaelic names and they are, in any case, easily confused with Heisker (the Monach Isles) or Hyskeir (Oigh Sgeir).

The larger islet, Haisgéir Mhor, is just under 17 hectares, or 41 acres, in area. It has a dramatic topography. There is a high plateau at the northern end called North Castle which is cut off from the rest by an overhanging cliff forming a forbidding barrier. Beside it is a natural rock arch and a collapsed sea cave. The southern half is intersected by a stunning rock arch forming a sea-tunnel some 43 metres in length and 10m in width. A lighthouse was constructed at the extreme south-westerly corner in 1997, a position 37.5m (123 ft) above sea level.

There are signs that the islet was populated in the past, although it may only have been seasonal. There is a spring of fresh water on North Castle. The area is quite well-protected from Atlantic storms and edible vitamin-rich sorrel and scurvey grass grow there. In June 2005, an expedition led by Nigel Winn spent two nights on Haisgéir Mhor. They discovered a grave in the southern part and the remains of a stone structure. On North Castle they found the remains of a small bothy. They also carried out a valuable survey and report on the island's birdlife.

The songs of North Uist tell of the Big Men of Haisgéir who were the sons of Odrum. It sounds like something from J R R Tolkein. The supposition by a number of historians is that the Big Men were the Norwegian Sjo-Same tribe from Lapland who were exiled and developed a nomadic lifestyle in their large ocean-going kayaks. These could easily cross the North Sea in the summer months. Our island mythology is certainly rife with magical stories of the "Finns" or "Finmen", particularly in the Northern Isles.

The belief is that the strangers possibly used Haisgéir Mhor as a safe base for their fishing and seal-hunting, but unlike the Vikings they kept very much to themselves. Their rare sighting by the indigenous islanders probably gave them a supernatural quality. It was said that they were seals which had taken on human form and particularly enjoyed dancing in the moonlight.

The women were very beautiful. But nothing's perfect: they smelled strongly of rotting fish.

The Scottish Islands, fully revised and updated, by Hamish Haswell-Smith (Canongate, £30)

NEED TO KNOW

Little Ross: Boats can be chartered from Clyde West Cruising in Ardrossan to Little Ross and the rest of the West Coast with a skipper or bareboat (without a skipper or crew), depending on your sailing experience and qualifications. For further information call 01505 843714 or visit www.clydewestcoastcruising.com. Kirkcudbright Marina provides safe anchorage and a peaceful haven on the Solway coast at a cost of £9 upwards per night. Power and water facilities are available at the pontoon along with shower facilities and fuel is available by request from road tankers. Call 01557 331 135 for more details. Provisions, repairs, Post Office, banks, and a wealth of pubs and restaurants, are available in the town.

Haisgeir Mohr and Haisgeir Eadach:

Alba Sailing in Oban provides charter boats to Haisgeir Mohr and Haisgeir Eadach, skippered or bareboat. You can make up part of a group or hire the boat privately. Call 01631 565 630 or visit www.alba-sailing.co.uk for details. For free information on tides throughout Scotland check www.bbc.co.uk/weather/coast/tides. Or order your own tide time-tables from www.laverpublishing.com.

Carbon footprint

There are about 0.03 tonnes of CO2 emitted on a return car journey from Glasgow to Oban.