As scholars of the early Americas revisit concepts like eye-witnessing and testimonial genres as sites of knowledge-making authority, incorporating insights from new work in the history of sensing in the early modern era (Tobin 2005, Maurette, forthcoming 2018), we would do well to consider how the practices of translation and the mechanics of early modern print culture undermine the claims of authors who profess to eye-witness experience. As a way of opening up new questions in the study of testimonial genres and narrative authority in vernacular scientific literatures, this paper analyzes the mistranslation of sensory knowledge in García d’Orta’s _Colóquios dos simples_ (Goa, 1563) and the remediation of images in the multiple editions of Gonzalo Fernández de Oviedo’s natural history of the Indies (1526, 1535, manuscript ca. 1539-1548, 1547).