“But it is not usual, you know, Miss Pogany,” he added, smiling. “As a matter of fact it is against the rules to be excused from school when it involves missing a lesson unless the pupil brings a written request from parent or guardian. So please remember to come armed with that if you wish to ask again.”

That was rather disconcerting with all the other Wednesdays stretching ahead. But for the nonce, Betty disregarded it. For to-day they were safe. And much as both Betty and Rose enjoyed school, it added something to the excitement of their adventure to leave the building just as the rest of their class was filing into the recitation room.

They seemed hardly to be on the train before they were off again. It was so short a ride, and money was so imperative, that Betty grudged the five cents apiece for their tickets. She had hardly taken out the doctor’s card to find the number on Parrot Street and returned it to her pocket, when the conductor shouted “Millville!” in the condescending manner in which she was to learn he always said it. It was a through train and express a great part of the distance it ran. Scarcely anyone ever got off at Millville, and yet something about the road forced every northbound train to stop there.

The main street had seemed last week untidy almost to the limit of possibility; but Parrot Street, which was really an alley, was as much worse as Main Street was worse than the wide, lovely avenue which was the principal street of South Paulding. Betty wondered if even the daring Rose wouldn’t have felt appalled had she been able to see it. But Rose only said “Quelque smell!” in her funny way and danced lightly over the uneven ridges of frozen mire.

The building whose sagging door bore traces of the number they sought was ramshackle indeed; the stairs were dark, rickety and dirty, and the corridor of the second story unventilated and ill-smelling. But they came to a clean-looking door with light shining through opaque glass, and though it had no designation on it, Betty was right in taking it for Dr. Vandegrift’s office. Within, it was neat and not unattractive. The doctor greeted them warmly like old friends.

“It cheers my heart to see such bright, happy faces,” he declared. “It does me good. It braces and strengthens me to combat the obloquy which pursues me. And the best of it is that I have the assurance of making it possible for Miss Rose to look upon Miss Betty’s yet happier face in the course of a few months.”

He moved out the chair upholstered in red plush which he had had at the Eagle Hotel, and gently helped Rose into it.

“Since I last saw you, young ladies. I have been reading certain eminent Hungarian authorities on the eye,” he went on, “and meditating on their conclusions, which are similar to my own, though in inventing my Galvano Eye-Cup, I have advanced a step—a long step—beyond them. I will only say what you have probably already inferred, that my confidence is unbounded.”

He wheeled the chair about, moved a small stand close to it and placed on it a heavy wooden box which he explained was his battery. Drawing down the blinds, he put a handle connected by wires with the box into each of the girl’s hands.

“Don’t grasp them. Hold them gently until I take them from you,” he bade her. Then he held a small glass cup to one of her eyes until it fastened itself there by suction. Ten minutes passed in absolute silence. During this period, Dr. Vandegrift kept his eyes constantly upon his patient, flash-light in hand and face very grave. Ever and anon he adjusted a glass over his eye and peered into Rose’s free eye. Rose, despite the warning, clutched the handles as for dear life. Betty’s heart throbbed wildly.