Tony - Are there any other 1s and 3s on the form that can be compared?
It looks like the number 3 on the age of people.
In addition, I have found that there was a No. 91 building at the rear and No.93 was on the street.
It looks like the numerator put down 91 and then changed it to 93.
However, it is interesting to note that the current shop is still a Chemist and is numbered 91.
Thanks for all your help and suggestions.