The thing is, it shouldn't be bound in a book. It should be in a type of loose leaf book with metal brads so documents can be taken in and out (yeah, like hello Sandypants). Back in the early days of birth record books, I'm talking the 1920s and 30s, they used prebound books but found out those didn't work so well. For one thing, the registrars are anal about dates so births for each year would never fit precisely within a pre-bound book. You'd have too few births to fill it during the calendar year or you'd have too many. So, they went with the loose leaf type so every calendar year or whatever their set dates were would all fit within a single book. The loose leaf would also allow for delayed births to be inserted within the birth year. Later, when people started using copy machines, the loose leaf style helped so that the clerk could removed the page to place it on the machine without damaging the entire book. Those books are heavy and with age will tear and they're just too cumbersome to copy with the page in it. Before copy machines, the clerk would retype the information onto a current blank bc form, so if forms changed then information may have not been included in the typed "copy" which is what this looks like since this one only has 23 boxes and the 1961 manual speaks to 46 which includes the birth weight, etc.
Also, that curved copy isn't exactly legal (and forget about it ever being a "true copy" of the original bc) because it doesn't show everything on the document. Case in point the handwritten numbers we can't read.
Back in the late eighties I happened to visit a couple of different county deeds registries to check on some properties. Houses generate a lot more official paper than babies do, but they were keeping the records bound in big fat books, nonetheless.
To find a deed, you first checked the grantor (seller) or grantee (buyer) indexes. In one of the registries, the grantor and grantee indexes were on a mixture of cards (recent) and books (covering ranges of years). The other registry was more advanced: in the lobby there was a bank of four or five IBM 3270 dumb terminals linked into a CICS application running on an IBM mainframe that retrieved the grantor - grantee data from indexed sequential files on disk.
In both cases, what was in the indexes was book and page numbers of documents, such as deeds, mortgages, liens, etc. Once you had a book and page number, you went off to the stacks, pulled down the book and turned to the page. E.g., book 5642, page 371. The books were big and heavy. They had a bank of coin-operated copiers onto which you could press down a book and copy a few pages. They were not loose-leaf, and you could see the curvature of the pressed-down paper in the copies.
Typically, the documents contained back links to earlier documents, which were also given in book and page form. So, it was off to the races. Literally a paper chase. I recall seeing multiple Motorola bag phones during my visit. I suspect they belonged to title company employees and paralegals chasing the paper for a living.