Bernese Adventure

Originally published in 1940 under the title Bernese Holiday [a tale]. Reissued in slightly abridged form as Bernese Adventure in 1953. The second in Jane Shaw's Holiday series.
"When Caroline, Sara, Venessa and John decide to take a holiday in the Bernese Oberland, little do they realize that their decision will set in motion a series of breath-taking adventures centered around the theft of a priceless necklace - the Phillmore Diamonds! Their lively escapades in the picturesque Swiss setting will delight, for Jane Shaw has drawn her characters with such understanding, they will endear themselves to the heart of every reader.The story combines their thrilling encounters and hilarious incidents so successfully that Bernese Adventure is a book that should command a place on every girl's bookshelf!"