While following clues from my great uncle Tom's postcard (see Message on a postcard) , I was keen to find out why he may have been in Scotland. A gazetteer of Scotland from the mid-1800s describes Craigo House (the address on the postcard) as "A fine mansion having offices, a large garden and some ornamental ground attached". Sadly, it seems Craigo House was demolished in the 1970s, though the lodge, some outbuildings and a walled garden still exist.
At around the time the postcard was sent (estimated to be about 1910/1911) Craigo House was owned by Mr and Mrs George McPhearson-Grant. Newspapers of the period mention various events at the property, from garden parties to Christmas celebrations but there is also mention of Craigo House being regularly rented by others for short periods, the excellent shooting and fishing on the estate being a particular draw.
A short piece in the Dundee Courier, in September 1908 reports that the butler at Craigo House, landed a salmon of 16½ pounds!
So perhaps Tom's employer, Colonel Thomas Hickman, was visiting Scotland for the fishing. It's clear from the postcard writer's comments that Tom had been away from the Wergs for more than just a few days, so it could be that the colonel had rented Craigo House for the whole summer.