The romance of hidden treasure has long been a subject of interest to A. Hyatt Verrill. In a previous book, 'Lost Treasure/' the author tracked down the existing treasures in South and Central America and along the Spanish Maine. In ''Secret Treasure," he gives a fascinating account of the hidden riches of the British Isles, a record which is based upon months of laborious research. As the author explains, in Great Britain there has been ample opportunity and motive for the hiding of possessions in the centuries that have passed and in the waves of warfare of one kind or another that have inundated the small islands. The scope of the story embraces England, Ireland, Scotland, and Wales, and includes accounts of such fabulous treasures as that of the Florencea Galleon whereon was lost the gold of the Armada, the treasure of the Tower of London, which Pepys writes about, and traditional treasures like Dick Wittington's and that of Wallingford Castle. "Secret Treasure" is an exciting adventure into a field which is perpetually romantic. It is told in a delightfully vivid manner. It is Mr. Verrill at his best.