"But, oh! the dust!" sighed Lyddy, trying to find a clean place on which to set the lamp. "Your grandfather must have been something of a chemist as well as a medical sharp," observed Harris, gazing about. "I'm curious to look this place over." "We ought to ask Aunt Jane," said Lyddy, doubtfully. "We really haven't any business in here." "She's never told us we shouldn't come," 'Phemie returned, quickly. "Now you young ladies sit down and keep still," commanded Harris, authoritatively, removing his coat and tying an apron around his waist--the apron being produced from his own pocket. "Now if you had your straw cuffs you'd look just as you used to----" "At the shop, eh?" finished Harris, when Lyddy caught herself up quick in the middle of this audible comment. "Ye-es." "So you _did_ notice me a bit when you were working around the little kitchen of that flat?" chuckled the young man. "Well!" gasped Lyddy. "I couldn't very well help remembering how you looked the night of the fire when you came sliding across to our window on that plank. _That_ was so ridiculous!" "Just so," responded Harris, calmly. "Now, please be still, young ladies and--watch the professor!" And for an hour the girls did actually manage to keep as still as mice. Their friend certainly was absorbed in the work before him. He tested one sample of water after another, and finally went back and did the work all over upon one particular bottle that he had brought down from Spink's hiding place among the rocks. "Just as I thought," he declared, with a satisfied smile. "And just as father suspected. Prepared to be surprised--pleasantly. Your Aunt Jane must be warned not to sell Hillcrest at _any_ price--just yet." "Oh, why not?" cried 'Phemie. "Because I believe there is a valuable mineral spring on it. This is a sample of it here. Mineral waters with such medicinal properties as this contains can be put on the market at an enormous profit for the owner of the spring. "I won't go into the scientific jargon of it now," he concluded. "But the spring is here--up there among the rocks. Spink knows where it is. That is his secret. _We_ must learn where the water flows from, and likewise, see to it that your Aunt Jane makes no sale of the place until the matter is well thrashed out and the value of the water privilege discovered." CHAPTER XXIX AN AUTOMOBILE RACE Lyddy was to write to Aunt Jane the next day. That was the decision when Harris started for town after breakfast, too. No time was to be lost in acquainting Aunt Jane with the fact that the old doctor spoke truly when he had said that "there were curative waters on Hillcrest."