“But, Jo, your face! You’re so hot.”

“Well, if you must know, I’ve been searching for the key with which to unlock the mystery—as Dr. Blackwell suggested.”

CHAPTER III
A NEW DISCOVERY

Looking cool and dainty in their fluffy summer dresses, the girls came lightly down the stairs, ready for their drive around the city.

Florence smiled as she noticed the car waiting at the curb. It had been rubbed and polished till it shone, and Felipe, beaming like a child with a favorite toy, was leaning over, brushing a speck of dust off the hood.

Snatching off his hat on seeing the girls and grinning widely, he hastened to open the door of the car; then, standing very straight, he waited for them to be seated. His effort to uphold the dignity of his position as chauffeur was amusing. After tilting his hat—an old one of Dr. Blackwell’s—at a rakish angle, he proudly took his place at the wheel. Although the car was not as new and expensive as some they passed, he was sure none carried more beautiful passengers.

To the girls’ delight it was much cooler now; soft breezes were stirring, and the heat was vanishing with the sun, which was sinking behind the high range of mountains to the west of the city.

Slowly Felipe passed the cathedral and circled the attractive little plaza, while the girls gazed admiringly at the formal beds of brilliant blooming flowers and drank in the perfumed air, heavy with the fragrance of wild orange and oleander. Now and then through the foliage of the trees they could catch a glimpse of the bandstand in the center of the trees.

“They have band concerts two nights a week here,” Florence explained. “We’ll promenade awhile tomorrow night. I know you’ll enjoy it.”

“Promenade? What do you mean?” asked Peggy.