To the best of my knowledge, there is no place online that gathers the various–freely available–Victorian and earlier cutting systems. Professional tailors–and cutters, which is a separate job, often in the same shop–use cutting systems rather than actual patterns.
The main difference, of course is in fit and style–a pattern may come graded to a number of sizes, but these are still ideal and won’t necessarily fit; cutting systems, on the other hand, use scales and mathematics to give proportions and how to draft for the body of the customer.
They typically also have notes on modifying the draft for varying postures and such. The majority of the systems were for menswear, and that is my focus–however, there were variations for tailored ladies’ clothing as well, and I will include those that I find.
To view the full list of tailoring manuals click Matsukaze Sewing Blog.