Back to Jacob typing at the terminal. Finger-thinking, toe-twitching rhythm; like the President of the United Federation of America, Jacob can't stop tapping his toes, his feet, even when going to sleep. Sometimes his entire knee shakes, and his teeth clatter, the desk moves... then a finger slips, and he types I rather than U, wrong letter right next to I on the keyboard, and then he has to calm down and do the spelling correction.     It was up to me to make sure that the gunsight displays worked.