Fletcher Pratt 
The Onslaught from Rigel 

Murray Lee woke abruptly, with the memory of the sound that had roused him drumming at the back of his head, though his conscious mind had been beyond its ambit. His first sensation was an overpowering stiffness in every muscle—a feeling as though he had been pounded all over, though his memory supplied no clue to the reason for such a sensation. Painfully, he turned over in bed and felt the left elbow where the ache seemed to center. He received the most tremendous shock of his life. The motion was attended by a creaking clang and the elbow felt exceedingly like a complex wheel. He sat up to make sure he was awake, tossing the offending arm free of the covers. The motion produced another clang and the arm revealed itself to his astonished gaze as a system of metal bands, bound at the elbow by the mechanism he had felt before, and crowned, where the fingers should be, by steely talons terminating in rubber-like finger-tips. Yet there seemed to be no lack of feeling in the member. For a few seconds he stared, open-mouthed, then lifted the other arm. It was the right-hand counterpart of the device he had been gazing at. He essayed to move one, then the other—the shining fingers obeyed his thought as though they were flesh and blood.