So we concocted an excellent scheme to keep them under constant observation, lest they should slip away again, as they did from the island. First of all, Amelia was to ask them to come and stop at the castle, on the ground that the rooms at the inn were uncomfortably small. We felt sure, however, that, as on a previous occasion, they would refuse the invitation, in order to be able to slink off unperceived, in case they should find themselves apparently suspected. Should they decline, it was arranged that Cesarine should take a room at the Cromarty Arms as long as they stopped there, and report upon their movements; while, during the day, we would have the house watched by the head gillie's son, a most intelligent young man, who could be trusted, with true Scotch canniness, to say nothing to anybody. To our immense surprise, Mrs. Forbes-Gaskell accepted the invitation with the utmost alacrity. She was profuse in her thanks, indeed; for she told us the Arms was an ill-kept house, and the cookery by no means agreed with her husband's liver. It was sweet of us to invite them; such kindness to perfect strangers was quite unexpected. She should always say that nowhere on earth had she met with so cordial or friendly a reception as at Seldon Castle. But--she accepted, unreservedly. "It _can't_ be Colonel Clay," I remarked to Charles. "He would never have come here. Even as David Granton, with far more reason for coming, he wouldn't put himself in our power: he preferred the security and freedom of the Cromarty Arms." "Sey," my brother-in-law said sententiously, "you're incorrigible. You _will_ persist in being the slave of prepossessions. He may have some good reason of his own for accepting. Wait till he shows his hand--and then, we shall understand everything." So for the next three weeks the Forbes-Gaskells formed part of the house-party at Seldon. I must say, Charles paid them most assiduous attention. He positively neglected his other guests in order to keep close to the two new-comers. Mrs. Forbes-Gaskell noticed the fact, and commented on it. "You are really too good to us, Sir Charles," she said. "I'm afraid you allow us quite to monopolise you!" But Charles, gallant as ever, replied with a smile, "We have you with us for so short a time, you know!" Which made Mrs. Forbes-Gaskell blush again that delicious blush of hers. During all this time the Professor went on calmly and persistently mineralogising. "Wonderful character!" Charles said to me. "He works out his parts so well! Could anything exceed the picture he gives one of scientific ardour?" And, indeed, he was at it, morning, noon, and night. "Sooner or later," Charles observed, "something practical must come of it."