We know nothing of the Nâtar, of which the Dînkart has no analysis.
The Gâh and Sîrôza may be derived from the Pâgag that treats of the Gâhânbârs and of the relations between the liturgy and the divisions of time.
The Rat-dât-îtag treats of the arrangement of the sacrifice. It is represented by two fragments[1].
The Baris is of an ethical character; the Kaskîsrav teaches how to prevent the sacrifice being ill-managed and turning to the benefit of the demons. No fragment has been referred to either of these two Nasks with any certainty[2].
The Vîstâsp-sâst or 'the Introduction of Vîstâsp,' treated of the conversion of Vîstâsp by Zoroaster and of his wars against Argâsp. It is represented by the Vîstâsp Yast (Yt. XXIV) and the Âfrin Paighambar Zartûst (Yt. XXIII). It is one of the sources of the Zardûst Nâma.
§ 6. From this rapid review we may draw the following conclusions:—
(i) Out of the twenty-one Nasks of the Sassanian A vesta, we possess two in their entirety (the Vendîdâd and the Stôt Yast) and the most important part of a third (the Bakân Yast).
(2) We have a considerable part of four Nasks: the Bak, the Hâdhôkht, the Vistâsp-sâst, and the Hûspâram; and several fragments of most of the others.
(3) We know indirectly, through the medium of Pahlavi translations or compilations, the contents of many Nasks of which we have few or no remnants in their original language: the Dâmdât, the Vistâsp-sâst, the Kitradât, and the Spand. In short we possess specimens, more or less considerable, of fifteen Nasks, and the complete text of the two Nasks which were considered all-important. For the Vendîdâd, being the book of purification; was to the priest the chief of the legal Nasks, and this is most
