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Middle-earth, or that (as shall be told) went back from exile into the West and dwelt and dwell now upon Eressea. In Valinor the ancient Elven-speech is maintained, and the Noldor never forsook it; but it became for them no longer a cradle-tongue, a mother-tongue, but a learned language of lore, and of high song and noble and solemn use.
    Few of the Sindar learned it, save in so far as they became, outside Doriath, merged in one people with Noldor and followed their princes; as indeed ere long happened indeed except for few scattered companies of Sindar in mountainous woods, and except also for the lordship of Cirdan, and the guarded kingdom of Thingol.
    Now this change of tongue among the Noldor took place for many divers reasons. First, that though the Sindar were not numerous they far outnumbered the hosts of Feanor and Fingolfin, such as in the end survived their dreadful journeys and reached Beleriand. Secondly and no less: that the Noldor having forsaken Aman themselves began to be subject to change undesigned while they were yet upon the march, and at the Rising of the Sun this change became swift - and the change in their daily tongue was such that, whether by reason of the like clime and soil and the like fortunes, whether by intercourse and mingling of blood, it changed in the same ways as did the Sindarin, and the two tongues grew towards one anotner. Thus it came that words taken from Noldorin into Telerin entered not in the true forms of High Speech but as it were altered and fitted to the character of the tongue of Beleriand. Thirdly: because after the death of Feanor the overlordship of the Exiles (as shall be recounted) passed to Fingolfin, and he being of other mood than Feanor acknowledged the high-kingship of Thingol and Menegroth, being indeed greatly in awe of that king, mightiest of the Eldar save Feanor only, and of Melian no less. But though Elu- Thingol, great in memory, could recall the tongue of the Eldar as it had been ere riding from Finwe's camp he heard the birds of Nan Elmoth, in Doriath the Sindarin tongue alone was spoken, and all must learn it who would have dealings with the king.
    It is said that it was after the Third Battle Dagor Aglareb (6) that the Noldor first began far and wide to take the Sindarin as they settled and established realms in Beleriand; though maybe the Noldorin survived (especially in Gondolin) until Dagor Arnediad (7) or until the Fall of Gondolin - survived, that is, in the spoken form that it had in Beleriand as different both from the Quenya (or Ancient Noldorin) and from the Sindarin: for the Quenya never perished and is known and used still by all such as crossed the Sea ere the Trees were slain.

    This is the first general linguistic statement since the Lhammas, written long before, and there have been major shihs from the earlier theory. The third version of the Lhammas, 'Lammasethen', the latest and shortest of the three, gives a clear statement of what is more diffusely expressed in the longer versions, and I cite a part of it (from V.193-4):

    Now ancient Noldorin, as first used, and written in the days of Feanor in Tun, remained spoken by the Noldor that did not leave Valinor at its darkening, and it abides still there, not greatly changed, and not greatly different from Lindarin. It is called Kornoldorin, or Finrodian because Finrod and many of his folk returned to Valinor and did not go to Beleriand. But most of the Noldor went to Beleriand, and in the 400 years of their wars with Morgoth their tongue changed greatly. For three reasons: because it was not in Valinor; because there was war and confusion, and much death among the Noldor, so that their tongue was subject to vicissitudes similar to those of mortal Men; and because in all the world, but especially in Middle-earth, change and growth was very great in the first years of the Sun. Also in Beleriand the tongue and dialects of the Telerian Ilkorins was current, and their king Thingol was very mighty;