This paper provides the solution to understanding the hitherto unknown writing system used for the manuscript listed as MS 408 at the Beinecke Library, Yale University. The writing system uses symbols, punctuation, grammar and language that are each unique. The manuscript is not encrypted, in the sense that its author made an effort to conceal the contents of the manuscript, as has been presumed by some scholars. Instead, it is code only in the sense that the modern reader needs to be versed in the calligraphic and linguistic rules to be able to translate and read the texts. Furthermore, in discovering its writing system, it became apparent that the manuscript is of invaluable importance to the study of the evolution of the Romance languages and the scheme of Italic letters and associated punctuation marks now commonplace in those and other modern languages. In short; it is revealed to be the only known document both written in Vulgar Latin, or proto-Romance, and using proto-Italic symbols. The original title for the manuscript, given by its female author, is: What one needs to be sure to acquire for the evils set in one’s fate. It is a book offering homeopathic advice and instruction to women of court on matters of the heart, of sexual congress, of reproduction, of motherhood and of the physical and emotional complications that can arise along the way through life. The manuscript has now been dated to the year 1444 and the location of its creation has been pinpointed to the court of Castello Aragonese, on the island of Ischia: as expounded in the companion paper Linguistically Dating and Locating Manuscript MS408: http://ling.auf.net/lingbuzz/003808.