Hi MC,
These are all baptism entries from church registers, not birth certificates. Civil registration of births did not start until 1856. The only extra info that you will likely find is a father's occupation and place of residence. Here is an example of a baptism transcription from Marilyn Rowan's website:
http://www.transcriptions.com.au/images/ebirth.pdfV1848594
67/1848 BINKS SARAH SYDNEY GRACE
Volume 67 is for Roman Catholic baptisms which took place in
1850. The register likely gives a birth year for the child of 1848. Was Sarah taken into a Catholic orphanage after the death of her father? This would probably explain the baptism and the guess of a birth year.
V1850416
141/1850 BINKS SARAH SYDNEY GRACE
The high volume numbers after volume 123 are usually Roman Catholic registers. These cannot be viewed on microfilm but must be ordered through the registry or a transcription agent. I believe this would be for the same baptism as above. I don't know if one would contain more info than the other, such as sponsor's names, but I would be more inclined to get the second one.
V18492937 39A/1849 BINKS SARAH SYDNEY GRACE
Volume 39 is for Church of England baptisms which took place in
1853. The "A" indicates that this entry is from the index which is sometimes found in the beginning of a register. The event is indexed under her year of birth and here is the corresponding entry on FamilySearch
https://familysearch.org/pal:/MM9.1.1/XTCL-PBWNot sure what is going on here. Perhaps she went to another family or back to her mother who had her baptised again.
Clear as mud?
Debra