420. Before the people knew anything of paper in these islands they wrote on the smooth bark of bamboo, or on leaves of the many palms which are found in these islands (and even yet this is done, in districts where there is no paper, or even that the schoolboys may not waste paper), the point of a knife or an iron, or some other material, serving as a pen (and now with birds' quills and ink). If it were a missive letter, they wrote it on palm-leaves, and folded it as we fold our letters. Some of them are much given to writing on the ground in a squatting posture, which is the usual way both men and women sit. 421. The cultured languages, as already stated, are six in number--for one cannot reckon the languages of the Negritos and mountain people as such, since each settlement has its own distinct language, which results from the lack of human intercourse. Among the cultured languages, the chief and mother languages are considered the Tagálog, the Pampanga, and the Visayan; and even among these the Tagálog is considered the most polished and powerful. That is not [for instance] because it lacks the tu [i.e., "thou"]--which is well employed with their primitive pronoun ycao or ca, even with persons to whom the greatest respect is due--but on account of the po and Po co, which explains it, and signifies "Sir" [señor mio]. The first is used for men, and the second for women. Interwoven with the words, it shows reverence and courtesy; as, for example, in order to answer "Yes" to a woman one says Oo, Po co, an expression which without the Po co would be too familiar. In many other phrases in the Tagálog language is shown its seriousness and polish; those who write grammars of the language will be able to set them forth.