The 125-year-old cottage school had run out of water after a drought in April and May forced the spring to run dry. Mrs Stephen’s husband hauled buckets of water from the sea to flush the loo while an approved plumber was called to the rescue.

The water crisis followed the prolonged battle over the four kilowatt generator and its inadeuate back-up batteries. A contractural dispute has so far left the primary without access to the island’s new electricity scheme.

Since one radiator swallows up three kilowatts, temperatures in winter struggle to climb above 50F in the 15ft- square classroom - vying to be the smallest in Scotland.

“What do you do if you want to spend time on the photocopier or computer? One day I went into the kitchen and cried,” Mrs Stephen admitted.