θησαυρόν: schol. “ἕρμαιον, εὕρημα”, taking it as merely ‘treasure trove’; but here ‘treasure’ evidently implies ‘store’ (cp. Ph. 37“θησαύρισμα”); the carrionbirds can return again and again to their feast.
εἰσορῶσι, when they look down upon it from the air. There is no ground for saying that “εἰσορᾶν” was specially ‘to eye with desire’: in Xen. Cyr. 5.1.15 “οὔτε πυρὸς ἅπτομαι οὔτε τοὺς καλοὺς εἰσορῶ”, it is simply ‘look at.’ The conjecture εἰσορμῶσι, to be taken with “πρὸς χάριν βορᾶς”, ‘swooping to the joy of the feast,’ is not only needless, but bad. Far finer is the picture of the birds pausing in their flight at the moment when they first descry the corpse below.
Take πρὸς χάριν βορᾶς with “γλυκὺν θησαυρόν”, not with “εἰσορῶσι”: lit., a welcome store to the birds, when they look upon it, with a view to pleasure in feeding. For the sensual use of “χάρις” cp. Phaedr. 254 A “τῆς τῶν ἀφροδισίων χάριτος.”
πρὸς χάριν is used either adverbially or with a genitive. (1) As an adverb, it means literally, ‘with a view to gratification’: hence (a) when the “χάρις” is one's own, ‘at pleasure,’ as Philoctetes calls the birds ( Ph. 1156) “κορέσαι στόμα πρὸς χάριν”, to glut their beaks on him ‘as they will’: (b) when the “χάρις” is another's, ‘so as to give pleasure,’ ‘graciously,’ as O. T. 1152 “σὺ πρὸς χάριν μὲν οὐκ ἐρεῖς”. (2) A genitive after “πρὸς χάριν” can denote (a) that in which the “χάρις” consists, as “βορᾶς” here: or (b) the person or thing whose the “χάρις” is, as below, 908, “τίνος νόμου...πρὸς χάριν”; ‘in deference to what law?’ Eur. Med. 538 “νόμοις τε χρῆσθαι μὴ πρὸς ἰσχύος χάριν”, ‘not at the pleasure of force,’— i.e. not so that force can do what it pleases. Here, “πρὸς χάριν βορᾶς” differs from a simple “χάριν βορᾶς” by implying the same notion as the adverbial “πρὸς χάριν” in Ph. 1156 quoted above: ‘to feast on at their pleasure.’—Eustathius on Il. 8.379 (p. 719. 9) defines carrion-birds as “τοῖς πρὸς χάριν ὁρῶσι βορᾶς τῆς ἀπὸ τῶν σαρκῶν”. It cannot be doubted that he was thinking of our passage, and that his text, like ours, had “εἰσορῶσι”: but, using the simple “ὁρῶσι”, he has made a new phrase, ‘looking to pleasure in food,’ and his words afford no argument for joining “πρὸς χάριν” with “εἰσορῶσι” here.