Puzzling birth certificate

[Anjeha]

I have a birth certificate issued in 1909.  The  father's name has been crossed out and the number (18) written above his forename and the number (19) above his surname.  Both are in brackets.  His surname is not the same as the mother's so presumably they weren't married.  Are these numbers a reference to something?  Can anyone help please?  I'm mystified.

[stanmapstone]

Hi Anjeha Welcome to RootsChat
This annotation is part of the system of doing corrections in registers. All corrections of a minor nature occurring at the time of the entry have to be numbered, obviously to prevent someone coming along later and altering an entry. Therefore, in this case, a correction was made in the entry at the time it was entered and are the 18th and 19th  such corrections in the register.
For errors discovered within a month of the entry being made then the registrar in the presence of the relevant parties, or in their absence in the presence of the Superintendent Registrar and two other credible witnesses, corrected the erroneous entry by entry in the margin, without making any alteration of the original entry, and signed the marginal entry, adding date when the correction was made.

Stan

[stanmapstone]

The instructions for Registration Act of 1875 state:
"The putative father of an illegitimate child cannot be required as father to give information respecting the birth. The name, surname and occupation of the putative father of an illegitimate child must not be entered except at the joint request of the father and mother; in which case both the father and mother must sign the entry as informants"

So it could be that his name was entered in error.

Stan

[Anjeha]

Hi Stan
Thanks very much for the welcome to RootsChat and for the answer to my query re the birth certificate.  For a genealogical search the 'mistake' is very much to my advantage but I wonder why the name was only crossed out rather than blanked out, although I'm most grateful it wasn't. 
Ann
 

[LizzieW]

I wonder why the name was only crossed out rather than blanked out

I guess in 1909 the registrar was more interested in correcting the errors, rather than deleting the "father's" name.  I don't suppose he thought that 100 years later someone would be looking at the records.   As you say it is to your advantage that the name was left in.

Lizzie