The g was a feature of Philippine orthography from the time the Doctrina Cristiana was printed in Manila in 1593 until around the 1960s, but no literature could be found that pertained to the rules that governed the usage of this letter or that explained its disappearance. This study was undertaken to determine the grammatical rules of its usage, as well as to document its origin, evolution, and eventual disappearance in the 1960s. Four samples of Tagalog literature (from the 16th, 19th, and 20th centuries) were obtained from which the occurrences as well as the non-occurrences of the g, were tabulated for analysis. It was determined that the usage of the g was dictated by how the words were pronounced and, as a consequence, it eventually fell into disuse when changes occurred in the way words containing the letter "ng" were spelled. In the end, the g was determined to have followed the life cycle of linguistic elements in that it is the need to represent speech sounds in writing that created it, and that its obsolescence caused its demise.