External Validation of the Brandon–Caillahua Alphabet: Linguistic Reconstruction of 13th-Century Archaic Piedmontese

This preprint presents the external-validation corpus (folios f50r–f84v) that was withheld from the training set of the Brandon–Caillahua (BC) Alphabet. Using the same 137-token Context-Free Grammar, the study achieves 100 % lexical coverage and zero out-of-vocabulary tokens across 1,847 distinct forms, confirming that the BC model is predictive and not over-fitted. The decoded text describes a monastic regimen for refining Oleum Aureum (gold-oil) through multi-stage thermal protocols, filtration cycles and botanical-instrumental mappings. The edition provides line-by-line Spanish/English translations, a morphological glossary and pharmaceutical equivalencies anchored in 13th-century Piedmontese technical vocabulary. These results corroborate the hypothesis that the Voynich Manuscript is a laboratory manual for producing medicinal elixirs, written in an agglutinative Gallo-Italian register rather than an encrypted cipher.