Herbert Weir Smyth, A Greek Grammar for Colleges

a. The substantive has an attribute: ““πολλῇ βοῇ προσέκειντο” they attacked with loud shouts” T. 4.127, παντὶ σθένει with all one's might 5. 23, ““τύχῃ ἀγαθῇ” with good fortune” C.I.A. /lref>So παντὶ (οὐδενὶ, ἄλλῳ, τούτῳ τῷ) τρόπῳ. Manner may be expressed by the adjective, as βιαίῳ θανάτῳ ἀποθνῄσκειν to die (by) a violent death X. Hi. 4.3 (= βίᾳ).

b. Many particular substantives have no attribute and are used adverbially: ““θεῖν δρόμῳ” to run at full speed” X. A. 1.8.19, βίᾳ by force, δίκῃ justly, δόλῳ by craft, (τῷ) ἔργῳ in fact, ἡσυχῇ quietly, κομιδῇ (with care) entirely, κόσμῳ in order, duly, κύκλῳ round about, (τῷ) λόγῳ in word, προφάσει ostensibly, σι_γῇ, σιωπῇ in silence, σπουδῇ hastily, with difficulty, τῇ ἀληθείᾳ in truth, τῷ ὄντι in reality, ὀργῇ in anger, φυγῇ in hasty flight.

N.—When no adjective is used, prepositional phrases or adverbs are generally employed: σὺν κραυγῇ, σὺν δίκῃ, μετὰ δίκης, πρὸς βία_ν (or βιαίως).

c. Here belongs the dative of feminine adjectives with a substantive (ὁδῷ, etc.) omitted, as ταύτῃ in this way, here, ἄλλῃ in another way, elsewhere, πῇ, ᾗ in what (which) way. So δημοσίᾳ at public expense, ἰδίᾳ privately, κοινῇ in common, πεζῇ on foot.

N.—Some of these forms are instrumental rather than comitative, e.g. ταύτῃ.