178. Prepositions are frequently used in Greek with the accusative, the locatival and instrumental dative, and the ablatival genitive; much less commonly (if at all) with the true genitive.
It may be shown (chiefly by comparison with Sanskrit) that the government of cases by prepositions belongs to a later stage of the language than the use of prepositions with verbs. In the first instance the case was construed directly with the verb, and the preposition did no more than qualify the verbal meaning. E. g. in such a sentence as εἰς Τροίην ἦλθε the accusative Τροίην originally went with ἦλθε. If however the construction Τροίην ἦλθε ceased to be usual except with εἰς, the preposition would be felt to be necessary for the accusative, i. e. would "govern" it.
In Homer we find many instances of a transitional character, in which a case form which appears to be governed by a preposition may equally well be construed directly with the verb—modified, it may be, in meaning by the preposition.
Thus we have ἀμφί with the dative in the recurring form
ἀμφὶ δʼ ἄρʼ ὤμοισιν βάλετο ξίφος
but the preposition is not necessary for the case, as we see from its absence in τόξʼ ὤμοισιν ἔχων, etc., and again from forms such as
ἀμφὶ δὲ χαῖται
περὶ μὲν ξίφος ἀργυρόηλον
where the preposition is best taken in the adverbial use.
Il. 17.523 ἐν δέ οἱ ἔγχος
νηδυίοισι μάλʼ ὀξὺ κραδαινόμενον λύε γυῖα
where ἐν is adverbial.
Again, we seem to have ἀμφί governing the accusative in
Il. 11.482 ὥς ῥα τότʼ ἀμφʼ Ὀδυσῆα . . . Τρῶες ἕπον
But ἀμφί must be taken with ἕπον.
Il. 11.776 σφῶϊ μὲν ἀμφὶ βοὸς ἕπετον κρέα
So in ὑπὸ ζυγὸν γαγε brought under the yoke the supposition of tmesis is borne out by the form ὕπαγε ζυγὸν ὠκέας ἵππους. And in the line
Il. 1.53 ἐννῆμαρ μὲν ἀνὰ στρατὸν ᾤχετο κῆλα θεοῖο
the rhythm is against taking ἀνὰ στρατόν together (§ 367.1), and points therefore to ἀνῴχετο.
Again, the ablatival genitive in
ἦλθʼ ἐξ ἁλός
came from the sea
may be explained like τείχεος ἐξελθεῖν, etc.; and in νηὸς ἀπὸ πρύμνης χαμάδις πέσε like νηὸς ἀποθρύσκων, and numerous similar constructions.
Thus the history of the usage of prepositions confirms the general principle laid down in a previous chapter (§ 131), that the oblique cases, with the exception of the true genitive, are primarily construed with verbs, and that consequently the construction of these cases with nouns and (we may nοw add) prepositions is always of a derivative kind.