This house was built around 1860, soon after the railway came to Helensburgh. Andrew Bonar Law - who was the British Prime Minister for only 7 months in 1922-23 - lived here from 1898 to 1909. Before that, it belonged to his wife's father. He had added the big staircase at the back in 1889 and his initials (his name was Harrington Robley) are on the weather-vane on top of the roof.
Andrew Bonar Law became a Member of Parliament in 1900, but lost his seat in 1906. When that happened, I'm told his 10-year-old daughter dressed up in a sack and daubed ashes from the fire onto her face before going to wait at the front gate (where the bungalow at the corner of West Stafford Street now is) for her father to come home :)
Andrew Bonar Law added the big stable block at the back of the house, and a billiard room on the other side of the house that's hidden from the road. Both of these, and the staircase, were designed by local architect William Leiper.