The lettering was just worn off the spine or wasn’t evenly stamped in when it was made. No way to know the maker without a tang stamp, might not even be one. Lots of razors in the Sheffield trade in the 19th century were “jobbing work”. Basically a forger would churn out a ton of blanks of the same blade which would then go to grinders and hefters (the men who did the scales) and were sold either unmarked, or a batch was divided up and multiple manufacturers would have basically the same razor but with their own mark put in by the forger.