Probably the most important collection of photographs I possess is this set, taken in 1900 by the American Emily Tuckerman. She visited the Tongue area in 1900 with her sister, Jane.
"The Machine! Jamie, Frank and the driver, Cousin Alfred and Cousin Rebecca Bolton, Bonnie Freda standing by wheel, ...

Emily has carefully documented each image.
"On the moors. Cousin Rebecca Bolton, Freda, and Jeanie, reading aloud ‘The Princess of Thule.” A background of purple heather. Near Tongue, Scotland. 1900. Taken and developed by Emily L Tuckerman."

The building in the first photograph, with the carriage, is now the Youth Hostel on the Kyle of Tongue. They obviously also gained access to the garden at Tongue House, which is owned by the Countess of Sutherland.
"The sundial in the lovely garden of the Lords of Ray – now the property of the Duke ...

The sundial can still be seen there.
"Another part of the garden, Tongue, Scotland, 1900. Jane and I passed seven (?) weeks in Tongue with the Boltons. Taken by Emily L Tuckerman and developed by her."

"A garden of the Lords of Ray in “Prince Charlie’s” time, now belonging to the Duke of Sutherland. Jane and I were in Tongue, 1900, with the Boltons."

The Tongue ferry operated until the causeway across the Kyle of Tongue was constructed in the 1970s.
"Tongue, Scotland. 1900. The ferry going between Melness and Tongue, the Kyle. While staying with the Boltons."

"The ferry bringing the sheep from Melness to Tongue, Scotland. 1900. When we were staying with the Boltons. Taken by Emily L Tuckerman."

"This is the way we went by the ferry from Tongue to Melness, Scotland. 1900. Jane and I were staying with the Boltons. He would drive in this machine with the dogs and keeper."

"Feeding her chickens as we passed her on the road, North Scotland. 1900. Taken and developed by Emily L Tuckerman."

"Feeding her chickens from a bowl of oatmeal. Scotland. 1900. Taken and developed by Emily L Tuckerman."

" 'I was born in Sutherland and married a Munro' – she lived in Tongue. We were staying with the Boltons in Tongue, Scotland. 1900. Taken and developed by ELT."

"Old Dolly in her doorway near Tongue, Scotland. 1900. When Jane and I were staying with the Boltons."

"Old Dolly in her little stone house – her peat fire – wee bit shawly over her head. She sat 2 minutes for this photo. Our dresses smelt of peat for months. In Scotland 1900. We put a sixpence under a tea cup on leaving, and she thought the fairies had been round. Taken and developed by Emily Lamb T...

"Old Tongue carpenter. Taken in his shop. Scotland, 1900. When we were staying with the Boltons. Taken and developed by Emily L Tuckerman."

"The old Carpenter, a McKay of course of Tongue, Scotland. 1900. Taken and developed by Emily Lamb Tuckerman, when we were staying with the Boltons."

"Old Sandy and the Pony. With a pile of peat, what the Scotch call “their winter flowers.” Tongue, Scotland. 1900. Taken and developed by Emily L Tuckerman."

"The house of the Precentor of Borgie Mains on the North Sea. North of Scotland, 1900. When Jane and I were with the Boltons. Taken and developed by Emily Lamb Tuckerman."

"Shepherd and sheep of Borgie Mains. Collie dog just near. Just(?) on the coast of the North Sea – Scotland. Cousin Rebecca, Jane, and Freda on the hill. 1900. Taken and developed by Emily L Tuckerman."

"As they walk down the road near Tongue, Scotland. 1900. Taken and developed by Emily L Tuckerman."

"Live(?) market on the roadside, near Tongue, Scotland. 1900. Taken & developed by Emily L Tuckerman."

The Tuckerman family seems to have been quite widespread in the USA.