Well, properly definied, "digital" means that the machine would be controlled by a processor that sees only 1's and 0's - and even the timing mechanism is digital. On an analog machine, the timer is controlled by an analog motor, which is always "on" when running. It's true that the tripping of various valves, solenoids, and relays is done via an off-or-on mechanism, but by definition the mechanical mechanism moves through a path described by whatever lever it's attached to, and so it's still an analog mechanism, not a digital one. It may be a type of computer, but it's a mechanical one, not a digital one. And in reality to be a computer it has to be programmable. IIRC, the earliest mechanical computers were the industrial looms of the 19th century that could be controlled by punched tapes, to produced complex Jacquard-type fabric designs.
