On the other hand, while phonetically the above explanation was not inconsistent with such cases as rka dkah, bkah, bska, and nga, rnga, ngag, sngags, lnga, ngad and brtse, brdzun, dbyar, &c., where the italicized letters are pronounced in full and the others are left aside, it failed to explain other cases, such as dgra, mgron, spyod, snyan, sbrang, sbrul, bkra, k'ri, krad, k'rims, k'rus, &c., pronounced da, don, cod, or swod, cen, Bang, deu, ta, t'i, tad or teh, tim, tu, &c., and many others, where the spoken forms are obviously the alteration by wear and tear of sounds originally similar to the written forms. Csoma de Koros, who was acquainted with the somewhat archaic sounds of Ladak, was able to point to only a few letters as silent.