Henry Horn's X-Ray Eye Glasses

Henry Horn had a new invention; a pair of glasses that worked on the x-ray principle. But he didn't expect them to reveal Nazi secret agents and their works of sabotage!
It's not enough to have a nudist colony move in next door! fumed Professor Paulsen. No, indeed! That wouldn't disrupt things enough. Now, in addition, every ne'er-do-well in the county comes prowling over our farm in order to spy on the naked numbskulls!
Scowling ferociously, the gaunt scientist stamped violently back across the meadow's lush verdure toward the little country home he shared with his partner, Henry Horn. Beside him, matching his own long strides, came the savant's old friend, Major Ray Coggleston of Army Intelligence.
None of us can hope for a bed of roses all the time, Joe, Coggleston remarked, grinning at the professor's outburst. 'Into each life some rain must fall,' you know. You've got trespassers to bother you. Me, I'm responsible for protecting one of the biggest explosives laboratories in the country against Axis espionage and sabotage.
Instinctively, as he spoke, the officer's eyes sought out the long, low Ordnance experiment station, barely a mile away. Professor Paulsen, following the glance, nodded.
You're right, he agreed. And when you come right down to it, my worries over the nudist camp back there —he jerked his head toward the high board fence which marked the boundary— aren't very important. Not with a war in progress.
By now the two were in the yard and rounding the corner of the house.
The next instant they stopped dead in their tracks.
There, in the shade of the building, stood a slight, familiar figure. A figure which, at the moment, was the center of attention for a little knot of interested spectators.
Oh, yes, gentlemen, it certainly does work! cried Henry Horn enthusiastically, his scraggly goatee jerking spasmodically with each nod of emphasis. He waved the battered pair of binoculars he clutched in his right hand. Yes, it's a marvelous invention. You can see everything you want to, just like you were right inside that camp. And only a dollar for a minute's look!