In an old and rare Spanish book, known by the title of “Las Preguntas del Almirante.” there are these two coplas.
Los que acostumbran al estudiar
y hallan el molde a la vista danoso,
dan por remedio el mas provechoso
en un fino espejo de azero mirar.
y pues vos en esto ya soys tan artista,
sabed que esta dubda me tiene perplexo,
de espejo que es concavo, o plano, o convexo,
qual dellos mejor conserva la vista?
Repuesta del Auctor.
A mi me paresce sin otra revista
que el espejo plano es mas conveniente,
porque a los ojos, si mucho no dista,
reflecte los rayos mas perfetamente.
Porque el convejo por su derredor
difunde los rayos que son visuales,
y el concavo en si incluye los tales,
por tanto el mas plano es mucho mejor.
100The Letrado, who propounds the question, says, that those persons who are accustomed to study, and find that the print hurts their eyes, recommend looking in a fine steel mirror as the best remedy, and he enquires what mirror will preserve the sight best… plane, concave, or convex. The author replies, that the plane mirror is best. This is the sum of the two coplas which I have given at full. In what manner can such a mirror possibly have been used?
As Nicolas Antonio did not know the name of the author from whose very singular work this is extracted, it may be worth while to mention, that it appears by an acrostic at the beginning of the sixth part, to have been Fray Luys d’Escobar. The book was first licensed in 1543, but he complains that it had been printed out of the kingdom without his knowledge, and in an incorrect state.